Remove mutable data from progressbar_kwargs argument in AnalysisBase.run()

[PicoCentauri]

Also I removed some trailing spaces and added a fixture for a universe in the test_base to clean them up a bit.

PR Checklist

• Tests?
• [ ] Docs?
• CHANGELOG updated?
• [ ] Issue raised/referenced?

Developers certificate of origin

• I certify that this contribution is covered by the LGPLv2.1+ license as defined in our LICENSE and adheres to the Developer Certificate of Origin.

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📚 Documentation preview 📚: https://mdanalysis--4459.org.readthedocs.build/en/4459/

[pep8speaks]

Hello @PicoCentauri! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2024-02-17 10:20:15 UTC

[github-actions]

Linter Bot Results:

Hi @PicoCentauri! Thanks for making this PR. We linted your code and found the following:

Some issues were found with the formatting of your code.

Code Location	Outcome
main package	⚠️ Possible failure
testsuite	⚠️ Possible failure

Please have a look at the darker-main-code and darker-test-code steps here for more details: https://github.com/MDAnalysis/mdanalysis/actions/runs/8166100470/job/22324308697

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Please note: The black linter is purely informational, you can safely ignore these outcomes if there are no flake8 failures!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.67%. Comparing base (d366921) to head (6a68dfb).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #4459      +/-   ##
===========================================
- Coverage    93.69%   93.67%   -0.03%     
===========================================
  Files          168      180      +12     
  Lines        21211    22292    +1081     
  Branches      3911     3912       +1     
===========================================
+ Hits         19873    20881    +1008     
- Misses         886      959      +73     
  Partials       452      452              

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[IAlibay]

lgtm thanks!

I'll give it a bit of time before merge in case anyone feels like this is API breaking, but I 100% support None over empty dictionary.

[PicoCentauri]

Thanks @IAlibay ! There is no rush with this.