java.lang.IllegalStateException: Failed to load property source from location 'file:./application.yml'

I am trying to run the exercise from here:
https://developer.okta.com/blog/2017/03/21/spring-boot-oauth
I’m getting the following error when trying to run the hellooAuth.groovy example.

I’m running Spring version Spring CLI v2.0.2.RELEASE
Java JDK 10.1
and SDKMAN 5.6.4+305

Michelles-MacBook-Pro:okta-oauth charlesmae$ spring run hellooAuth.groovy
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.codehaus.groovy.vmplugin.v7.Java7$1 (jar:file:/Users/charlesmae/.sdkman/candidates/springboot/2.0.2.RELEASE/lib/spring-boot-cli-2.0.2.RELEASE.jar!/BOOT-INF/lib/groovy-2.4.15.jar!/) to constructor java.lang.invoke.MethodHandles$Lookup(java.lang.Class,int)
WARNING: Please consider reporting this to the maintainers of org.codehaus.groovy.vmplugin.v7.Java7$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
21:10:28.735 [runner-0] DEBUG org.springframework.boot.context.logging.ClasspathLoggingApplicationListener - Application failed to start with classpath: []
21:10:28.883 [background-preinit] DEBUG org.hibernate.validator.messageinterpolation.ResourceBundleMessageInterpolator - Loaded expression factory via original TCCL
21:10:28.892 [background-preinit] DEBUG org.hibernate.validator.internal.engine.ValidatorFactoryImpl - HV000234: Using org.hibernate.validator.messageinterpolation.ResourceBundleMessageInterpolator as ValidatorFactory-scoped message interpolator.
21:10:28.892 [background-preinit] DEBUG org.hibernate.validator.internal.engine.ValidatorFactoryImpl - HV000234: Using org.hibernate.validator.internal.engine.resolver.TraverseAllTraversableResolver as ValidatorFactory-scoped traversable resolver.
21:10:28.892 [background-preinit] DEBUG org.hibernate.validator.internal.engine.ValidatorFactoryImpl - HV000234: Using org.hibernate.validator.internal.util.ExecutableParameterNameProvider as ValidatorFactory-scoped parameter name provider.
21:10:28.892 [background-preinit] DEBUG org.hibernate.validator.internal.engine.ValidatorFactoryImpl - HV000234: Using org.hibernate.validator.internal.engine.DefaultClockProvider as ValidatorFactory-scoped clock provider.
21:10:28.892 [background-preinit] DEBUG org.hibernate.validator.internal.engine.ValidatorFactoryImpl - HV000234: Using org.hibernate.validator.internal.engine.scripting.DefaultScriptEvaluatorFactory as ValidatorFactory-scoped script evaluator factory.
21:10:29.554 [runner-0] ERROR org.springframework.boot.SpringApplication - Application run failed
java.lang.IllegalStateException: Failed to load property source from location ‘file:./application.yml’
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:537)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadForFileExtension(ConfigFileApplicationListener.java:496)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:464)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$null$6(ConfigFileApplicationListener.java:446)
at java.base/java.lang.Iterable.forEach(Iterable.java:75)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$load$7(ConfigFileApplicationListener.java:445)
at java.base/java.lang.Iterable.forEach(Iterable.java:75)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:442)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:330)
at org.springframework.boot.context.config.ConfigFileApplicationListener.addPropertySources(ConfigFileApplicationListener.java:212)
at org.springframework.boot.context.config.ConfigFileApplicationListener.postProcessEnvironment(ConfigFileApplicationListener.java:195)
at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEnvironmentPreparedEvent(ConfigFileApplicationListener.java:182)
at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEvent(ConfigFileApplicationListener.java:168)
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:74)
at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54)
at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:358)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:317)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.springframework.boot.cli.app.SpringApplicationLauncher.launch(SpringApplicationLauncher.java:69)
at org.springframework.boot.cli.command.run.SpringApplicationRunner$RunThread.run(SpringApplicationRunner.java:173)
Caused by: org.yaml.snakeyaml.scanner.ScannerException: mapping values are not allowed here
in ‘reader’, line 6, column 21:
accessTokenUri: https://dev-865953-admin.oktap
^

at org.yaml.snakeyaml.scanner.ScannerImpl.fetchValue(ScannerImpl.java:872)
at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:360)
at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:226)
at org.yaml.snakeyaml.parser.ParserImpl$ParseBlockMappingKey.produce(ParserImpl.java:557)
at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:157)
at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:147)
at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:227)
at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:154)
at org.yaml.snakeyaml.composer.Composer.composeValueNode(Composer.java:249)
at org.yaml.snakeyaml.composer.Composer.composeMappingChildren(Composer.java:240)
at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:228)
at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:154)
at org.yaml.snakeyaml.composer.Composer.composeValueNode(Composer.java:249)
at org.yaml.snakeyaml.composer.Composer.composeMappingChildren(Composer.java:240)
at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:228)
at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:154)
at org.yaml.snakeyaml.composer.Composer.composeDocument(Composer.java:122)
at org.yaml.snakeyaml.composer.Composer.getNode(Composer.java:84)
at org.yaml.snakeyaml.constructor.BaseConstructor.getData(BaseConstructor.java:123)
at org.yaml.snakeyaml.Yaml$1.next(Yaml.java:547)
at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:168)
at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:141)
at org.springframework.boot.env.OriginTrackedYamlLoader.load(OriginTrackedYamlLoader.java:75)
at org.springframework.boot.env.YamlPropertySourceLoader.load(YamlPropertySourceLoader.java:50)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadDocuments(ConfigFileApplicationListener.java:547)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:517)
... 26 common frames omitted

java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.springframework.boot.cli.app.SpringApplicationLauncher.launch(SpringApplicationLauncher.java:69)
at org.springframework.boot.cli.command.run.SpringApplicationRunner$RunThread.run(SpringApplicationRunner.java:173)
Caused by: java.lang.IllegalStateException: Failed to load property source from location ‘file:./application.yml’
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:537)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadForFileExtension(ConfigFileApplicationListener.java:496)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:464)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$null$6(ConfigFileApplicationListener.java:446)
at java.base/java.lang.Iterable.forEach(Iterable.java:75)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.lambda$load$7(ConfigFileApplicationListener.java:445)
at java.base/java.lang.Iterable.forEach(Iterable.java:75)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:442)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:330)
at org.springframework.boot.context.config.ConfigFileApplicationListener.addPropertySources(ConfigFileApplicationListener.java:212)
at org.springframework.boot.context.config.ConfigFileApplicationListener.postProcessEnvironment(ConfigFileApplicationListener.java:195)
at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEnvironmentPreparedEvent(ConfigFileApplicationListener.java:182)
at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEvent(ConfigFileApplicationListener.java:168)
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:74)
at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54)
at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:358)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:317)
… 6 more
Caused by: mapping values are not allowed here
in ‘reader’, line 6, column 21:
accessTokenUri: https://dev-865953-admin.oktap
^

at org.yaml.snakeyaml.scanner.ScannerImpl.fetchValue(ScannerImpl.java:872)
at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:360)
at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:226)
at org.yaml.snakeyaml.parser.ParserImpl$ParseBlockMappingKey.produce(ParserImpl.java:557)
at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:157)
at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:147)
at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:227)
at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:154)
at org.yaml.snakeyaml.composer.Composer.composeValueNode(Composer.java:249)
at org.yaml.snakeyaml.composer.Composer.composeMappingChildren(Composer.java:240)
at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:228)
at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:154)
at org.yaml.snakeyaml.composer.Composer.composeValueNode(Composer.java:249)
at org.yaml.snakeyaml.composer.Composer.composeMappingChildren(Composer.java:240)
at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:228)
at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:154)
at org.yaml.snakeyaml.composer.Composer.composeDocument(Composer.java:122)
at org.yaml.snakeyaml.composer.Composer.getNode(Composer.java:84)
at org.yaml.snakeyaml.constructor.BaseConstructor.getData(BaseConstructor.java:123)
at org.yaml.snakeyaml.Yaml$1.next(Yaml.java:547)
at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:168)
at org.springframework.beans.factory.config.YamlProcessor.process(YamlProcessor.java:141)
at org.springframework.boot.env.OriginTrackedYamlLoader.load(OriginTrackedYamlLoader.java:75)
at org.springframework.boot.env.YamlPropertySourceLoader.load(YamlPropertySourceLoader.java:50)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.loadDocuments(ConfigFileApplicationListener.java:547)
at org.springframework.boot.context.config.ConfigFileApplicationListener$Loader.load(ConfigFileApplicationListener.java:517)
... 26 more

My bet is - something wrong with indentation in your yml file. Double check the configuration