ci: add a script to estimate unit test coverage

[hisImminence]

Which problem does the PR fix?

Trying to estimate our unit test coverage by a self-made script (used heavily copilot 🎉 ):

• It takes all config options from the values.yaml that are flagged with @params or @extra
• It takes all config options set in our unit tests
• Matches the 2 lists
• Generate an output:
  • print out unmatched values of the values.yaml
  • print out unmatched values of the unit test
  • Calculates test scores:

The result looks like follows:

What's in this PR?

Checklist

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