[ENH] update gha

[arnaudbore]

Quick description

Please include a summary of the changes and the related issue(s) or improvement(s).
Please also include relevant motivation and context. List any dependencies that are required for this change if needed.

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Type of change

Check the relevant options.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Provide data, screenshots, command line to test (if relevant)

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Checklist

• My code follows the style guidelines of this project (run autopep8)
• I added relevant citations to scripts, modules and functions docstrings and descriptions
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I moved all functions from the script file (except the argparser and main) to scilpy modules
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.59%. Comparing base (b2bf4ac) to head (c20e3b2).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1341      +/-   ##
==========================================
- Coverage   72.60%   72.59%   -0.02%     
==========================================
  Files         301      301              
  Lines       26276    26276              
  Branches     3699     3699              
==========================================
- Hits        19078    19075       -3     
  Misses       5648     5648              
- Partials     1550     1553       +3     

Flag	Coverage Δ
smoketests	69.75% <ø> (-0.02%)	⬇️
unittests	14.21% <ø> (ø)

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

Components	Coverage Δ
Scripts	75.32% <ø> (-0.03%)	⬇️
Library	69.31% <ø> (ø)

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[AlexVCaron]

Everything looks clean ! The only contentious point would've been the artifacts actions versions, which are well aligned.

Eventually, I'd suggest reassembling the base, ml and tutorial tests under the same workflow using a matrix, to have them part of the same coverage report. But it's a non-issue.

LGTM 🚀