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[Zeitsperre]

Pull Request Checklist:

• This PR addresses an already opened issue (for bug fixes / features)
  • This PR fixes #xyz
• (If applicable) Documentation has been added / updated (for bug fixes / features).
• (If applicable) Tests have been added.
• CHANGES.rst has been updated (with summary of main changes).
  • Link to issue (:issue:number) and pull request (:pull:number) has been added.

What kind of change does this PR introduce?

• Updates the template to the latest commit
• GitHub Workflows now point to commits rather than tags
• Dependabot will now only update on a monthly schedule
• Dependencies have been updated and synchronized

Does this PR introduce a breaking change?

Yes.

• CHANGES.rst is now CHANGELOG.rst
• The package now uses a src layout in lieu of a flat layout
• Maintainer-specific directions are now found under releasing.rst

Other information:

https://packaging.python.org/en/latest/discussions/src-layout-vs-flat-layout/
https://keepachangelog.com/en/1.0.0/