injectCredentialsAndInvoke doesn't support void returns.

[rjlohan]

e.g; an API call to setBucketNotificationConfiguration for S3 returns void, hence the proxy call cannot support this API.

[rjlohan]

Should also note that this is only an issue when using the v1 SDK; v2 has correct base typing across S3 APIs.

[johnttompkins]

Should just need to add a void version of the method here: https://github.com/aws-cloudformation/cloudformation-cli-java-plugin/blob/master/src/main/java/software/amazon/cloudformation/proxy/AmazonWebServicesClientProxy.java?

[ammokhov]

so since aws sdk v2 has different model it always returns a response, so the change needs to be made in here - https://github.com/aws-cloudformation/cloudformation-cli-java-plugin/blob/master/src/main/java/software/amazon/cloudformation/proxy/AmazonWebServicesClientProxy.java#L439-L455