test(cz_customize): add missing YAML configuration file tests

[AdrianDC]

Partial rebase of #1207 for tests commits made last summer.

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :warning: Please upload report for BASE (v4-9-2@69d32cf). Learn more about missing BASE report.

Additional details and impacted files

@@            Coverage Diff            @@
##             v4-9-2    #1516   +/-   ##
=========================================
  Coverage          ?   98.71%           
=========================================
  Files             ?       60           
  Lines             ?     2655           
  Branches          ?        0           
=========================================
  Hits              ?     2621           
  Misses            ?       34           
  Partials          ?        0           

Flag	Coverage Δ
unittests	98.71% <ø> (?)

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[AdrianDC]

Rebased from last year's PR, to update towards 4.9.1+adriandc.20250914 for pre-commit-crocodile 8.0.0 (prek becoming default btw).

Feel free to edit the PR or cherry-pick at will.

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For the record, I'm not a fan of pinning to a patched & customized fork for so long, blocking my users + coworkers on a specific version of commitizen-tools that I rebase 2-3 times a year, including now v5-moved fixes and questions features, but works fine since August 2024.