fix(cli): handle argparse different behavior after python 3.9

[Lee-W]

Description

argparse raises TypeError when non exist command is provided on Python < 3.9
but raise SystemExit with exit code == 2 on Python 3.9
this error does not break anything obviously from the user perspective, but will break our existing test

#429

This issue is caused by https://bugs.python.org/issue29298. The new checking is the correct one, but we'll need to keep the old one for backward compatibility. This fix was first introduced on 3.9.7 👉 see argparse.py#L730-L731

Checklist

• Add test cases to all the changes you introduce
• Run ./script/format and ./script/test locally to ensure this change passes linter check and test
• Test the changes on the local machine manually
• Update the documentation for the changes

Expected behavior

detailed on #429

Steps to Test This Pull Request

detailed on #429

Additional context

[codecov]

Codecov Report

Merging #430 (ca0e4bc) into master (9924180) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #430   +/-   ##
=======================================
  Coverage   97.90%   97.90%           
=======================================
  Files          39       39           
  Lines        1382     1384    +2     
=======================================
+ Hits         1353     1355    +2     
  Misses         29       29           

Flag	Coverage Δ
unittests	97.90% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
commitizen/cli.py	97.61% <100.00%> (+0.11%)	⬆️

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