feat: add permissions for ECR Public container pulls to Auto Mode NodeRole

[fletcherw]

Update the default EKS Auto Mode Node Role to allow authenticated pulls from ECR public. This ensures that container pulls are not unnecessarily throttled due to unauthenticated pulls.

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
• Made sure the title of the PR is a good description that can go into the release notes

[github-actions]

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