Add tool to manage branch protection rules across many repositories

We currently have a branch protection rule in place that protects "release-*" branches in our repositories.

This has drawbacks:

• it will cause release scripts to fail because the newly created release branches cannot be pushed to by the script
• prs on these branches cannot use the merge queue (not possible with wildcards in the branch name)

It might be worth switching to individual protection rules for every release, but that would make them hard to change/administer.

The github api allows managing these rules: https://docs.github.com/en/rest/branches/branch-protection?apiVersion=2022-11-28

We should look into writing a simple python script that takes a list of repos and release names and updates these protection rules.

Beginne mit der im Issue verknüpften GitHub branch protection REST API und ermittle, wie Schutzregeln für mehrere Repositories verwaltet werden können. Definiere die Eingaben des Skripts als Listen von Repositories und Release-Namen; fertig ist die Aufgabe, wenn die Regeln zentral aktualisiert werden können, ohne auf den release-* Wildcard zu setzen, sodass Release-Pushes und Merge-Warteschlangen funktionieren.