Pre-0.0.27 release

[Zeitsperre]

Description

This Pull Request updates several GitHub Actions versions in order to ensure that Workflows remain working. It also removes the now-obsolete requirements.txt, updates the pre-commit hook versions, and runs the formatter tools over the library to ensure consistency.

Documentation has been slightly changed to reflect the new release procedure and I have also cherry-picked 325c5d4 from @weipeng1999 in order to fast-track changes from them (closes #422).

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• Documentation
• refactoring

How Has This Been Tested?

$ pytest
$ pre-commit run -a

Pre-Merge Checklist (final steps)

• I have rebased onto main or develop (wherever I am merging) and dealt with any conflicts.
• I have squashed commits to a reasonable amount, and force-pushed the squashed commits.

References

N/A

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[codecov]

Codecov Report

❌ Patch coverage is 90.72165% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.55%. Comparing base (d5af7f0) to head (ca329e0).
⚠️ Report is 14 commits behind head on main.

Files with missing lines	Patch %	Lines
xskillscore/tests/test_skipna_functionality.py	70.83%	7 Missing ⚠️
xskillscore/core/comparative.py	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #428      +/-   ##
==========================================
- Coverage   94.76%   94.55%   -0.22%     
==========================================
  Files          27       27              
  Lines        2809     2829      +20     
==========================================
+ Hits         2662     2675      +13     
- Misses        147      154       +7     

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[Zeitsperre]

@aaronspring @raybellwaves

If we want to make a release right after this PR, the last thing we need to do is update the Changelog date. If we can do that here when merging, there's no need to open another Pull Request (we just need to tag main).

Thanks again!