modify CreateFeatureGroup API call to accept _both_ KmsKeyId and KmsKeyId_ARN.

[sermolin]

Describe the feature you'd like
In CreateFeatureGroup, the parameter "KmsKeyId" expects KMS Key ID ARN, instead of the KmsKeyId value. This behavior is different from other API calls. This is not just a documentation issue. This inconsistency becomes a serious problem when someone tries to pass KMS Key to all SageMaker API calls either via either AWS Systems Manager Parameter Store or by encapsulating KMS Key in a SageMaker SuperSession object.

How would this feature be used? Please describe.
To preserve backwards compatibility, modify CreateFeatureGroup API call to accept both KmsKeyId and KmsKeyId_ARN.

Describe alternatives you've considered
This seems to be the best solution

Additional context
https://t.corp.amazon.com/V408655442/communication

[akrishna1995]

We have added your feature request to our backlog of feature requests and may consider putting it into future SDK versions. I will go ahead and close the issue now, please let me know if you have any more feedback.