feat: unpin apk packages, remove overcommit, switch back to github runners

[rwaffen]

• apk packages are always latest in alpine
• overcommit was never used properly
  • and i dont see the usage in a container
  • overcommit installs local git hooks
• switch back to github runners
  • our own runners fail to often and i dont get it debugged

[github-advanced-security]

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