Remove push-buildpackage workflow from syncignore

[jericop]

Summary

This change:

• Removes push-buildpackage workflow from .github/syncignore
  • This is needed to publish multi-arch images. Right not it's still publishing single-architecture images.
• Manually syncs changes from github-config repo

Use Cases

Checklist

• I have viewed, signed, and submitted the Contributor License Agreement.
• I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• I have added an integration test, if necessary.
• I have reviewed the styleguide for guidance on my code quality.
• I'm happy with the commit history on this PR (I have rebased/squashed as needed).