test(commands): centralize all --help tests in a file to dedup code

[bearomorphism]

Test improvements

1. Addressed the issues about missing skip_below_py_3_13 and missing forced consistent environment variables to reduce the chance of unnecessary file regression test failures.
2. Extracted duplicated logics.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

@@            Coverage Diff             @@
##             v4-11-0    #1726   +/-   ##
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  Coverage           ?   97.84%           
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  Files              ?       60           
  Lines              ?     2604           
  Branches           ?        0           
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  Hits               ?     2548           
  Misses             ?       56           
  Partials           ?        0           

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[bearomorphism]

The variable name itself does not reflect why we want to set this variable... this may make it hard for future contributors to understand the code correctly

[bearomorphism]

Copied from AI output. I know COLUMNS is necessary, but not sure for the rest

[bearomorphism]

@woile @Lee-W could you review this PR when you have a moment? This PR contains the resolution of error when someone is trying to update CLI --help description. Some other PRs updating CLI options have dependencies on this PR.

Thanks!

[woile]

I don't understand what this is supposed to fix

[bearomorphism]

I don't understand what this is supposed to fix

The behavior of --help of argparse is different in some cases between python 3.13 and below 3.13 as the message of original skip_below_py_3_13 says. Some of --help tests still uses skip_below_py_3_10 before this PR, and those tests still pass in the pipeline luckily.

When we try to add new options to the CLI, the help text changes, and usually we run pytest --regen-all to regenerate the file_regression test file, but the regenerated content may be different depends on the local environment (monkeypatch in this PR addresses this issue).

[bearomorphism]

The following pipeline result is a false alarm test failure caused by forgetting to skip the test below python 3.13.

https://github.com/commitizen-tools/commitizen/actions/runs/20207591917/job/58008470452?pr=1724

Test passes for python version 3.13, 3.14 but not on 3.10

This PR can fix it.