Hey, I'm using the plugin for IAM Role Access instead of an Access Key / Secret Access Key access scheme - which according to the docs (and up until a week ago) worked smoothly.

I've recently updated the plugin, and since then I get this error -

```

java.lang.NullPointerException: Access key ID cannot be blank. at PluginClassLoader for aws-java-sdk2-core//software.amazon.awssdk.utils.Validate.notNull(Validate.java:119) at PluginClassLoader for aws-java-sdk2-core//software.amazon.awssdk.auth.credentials.AwsBasicCredentials.<init>(AwsBasicCredentials.java:68) at PluginClassLoader for aws-java-sdk2-core//software.amazon.awssdk.auth.credentials.AwsBasicCredentials.<init>(AwsBasicCredentials.java:43) at PluginClassLoader for aws-java-sdk2-core//software.amazon.awssdk.auth.credentials.AwsBasicCredentials$Builder.build(AwsBasicCredentials.java:238) at PluginClassLoader for aws-java-sdk2-core//software.amazon.awssdk.auth.credentials.AwsBasicCredentials.create(AwsBasicCredentials.java:100) at PluginClassLoader for aws-credentials//com.cloudbees.jenkins.plugins.awscredentials.AWSCredentialsImpl.resolveCredentials(AWSCredentialsImpl.java:170) at PluginClassLoader for aws-credentials//com.cloudbees.jenkins.plugins.awscredentials.AWSCredentialsImpl.getCredentials(AWSCredentialsImpl.java:236) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutor.getCredentialsFromContext(AmazonHttpClient.java:1295) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutor.runBeforeRequestHandlers(AmazonHttpClient.java:869) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutor.doExecute(AmazonHttpClient.java:818) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeWithTimer(AmazonHttpClient.java:805) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutor.execute(AmazonHttpClient.java:779) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutor.access$500(AmazonHttpClient.java:735) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient$RequestExecutionBuilderImpl.execute(AmazonHttpClient.java:717) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:581) at PluginClassLoader for aws-java-sdk-minimal//com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:559) at PluginClassLoader for aws-java-sdk-ecr//com.amazonaws.services.ecr.AmazonECRClient.doInvoke(AmazonECRClient.java:3770) at PluginClassLoader for aws-java-sdk-ecr//com.amazonaws.services.ecr.AmazonECRClient.invoke(AmazonECRClient.java:3737) at PluginClassLoader for aws-java-sdk-ecr//com.amazonaws.services.ecr.AmazonECRClient.invoke(AmazonECRClient.java:3726) at PluginClassLoader for aws-java-sdk-ecr//com.amazonaws.services.ecr.AmazonECRClient.executeGetAuthorizationToken(AmazonECRClient.java:1939) at PluginClassLoader for aws-java-sdk-ecr//com.amazonaws.services.ecr.AmazonECRClient.getAuthorizationToken(AmazonECRClient.java:1907) at PluginClassLoader for amazon-ecr//com.cloudbees.jenkins.plugins.amazonecr.AmazonECSRegistryCredential.getPassword(AmazonECSRegistryCredential.java:157) at PluginClassLoader for amazon-ecr//com.cloudbees.jenkins.plugins.amazonecr.AmazonECSRegistryTokenSource.convert(AmazonECSRegistryTokenSource.java:52) at PluginClassLoader for amazon-ecr//com.cloudbees.jenkins.plugins.amazonecr.AmazonECSRegistryTokenSource.convert(AmazonECSRegistryTokenSource.java:37) at PluginClassLoader for authentication-tokens//jenkins.authentication.tokens.api.AuthenticationTokens.convert(AuthenticationTokens.java:148) at PluginClassLoader for authentication-tokens//jenkins.authentication.tokens.api.AuthenticationTokens.convert(AuthenticationTokens.java:110) at PluginClassLoader for docker-plugin//com.nirima.jenkins.plugins.docker.DockerCloud.getAuthConfig(DockerCloud.java:954) at PluginClassLoader for docker-plugin//com.nirima.jenkins.plugins.docker.DockerCloud.setRegistryAuthentication(DockerCloud.java:931) at PluginClassLoader for docker-plugin//com.nirima.jenkins.plugins.docker.DockerTemplate.pullImage(DockerTemplate.java:659) at PluginClassLoader for docker-plugin//com.nirima.jenkins.plugins.docker.DockerTemplate.provisionNode(DockerTemplate.java:687) at PluginClassLoader for docker-plugin//com.nirima.jenkins.plugins.docker.DockerCloud$1.run(DockerCloud.java:414) at jenkins.util.ContextResettingExecutorService$1.run(ContextResettingExecutorService.java:28) at jenkins.security.ImpersonatingExecutorService$1.run(ImpersonatingExecutorService.java:68) at jenkins.util.ErrorLoggingExecutorService.lambda$wrap$0(ErrorLoggingExecutorService.java:51) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.base/java.util.concurrent.FutureTask.run(Unknown Source) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.base/java.lang.Thread.run(Unknown Source)

```

(My usage is for logging into an ECR registry)

Since nothing else changed, I'm inclinec to believe the Java SDK update in the latest version may have blocked this feature. Thanks in advance,