fix: only add ECR Public perms in aws partition

[fletcherw]

Description

ECR Public doesn't exist in all partitions, so filter it out when creating clusters elsewhere.

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the userdocs directory)
• Manually tested
  • create Auto cluster in aws-us-gov and aws partition, validated ECR public policy appeared only in aws.
• Made sure the title of the PR is a good description that can go into the release notes

[github-actions]

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