chore: Removed some CI jobs with macOS

[fg-mindee]

Unfortunately, the CI is getting slower by the way and the suspect is mostly macOS jobs. This PR keeps macOS jobs to build the project and collect environment but removes the rest to speed up PR CI jobs.

Any feedback is welcome!

[codecov]

Codecov Report

Merging #470 (4635285) into main (8660b4b) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #470      +/-   ##
==========================================
+ Coverage   95.80%   95.81%   +0.01%     
==========================================
  Files          95       95              
  Lines        4000     3992       -8     
==========================================
- Hits         3832     3825       -7     
+ Misses        168      167       -1     

Flag	Coverage Δ
unittests	95.81% <ø> (+0.01%)	⬆️

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

Impacted Files	Coverage Δ
doctr/models/recognition/sar/pytorch.py	98.34% <0.00%> (-0.03%)	⬇️
doctr/models/recognition/crnn/pytorch.py	98.91% <0.00%> (-0.03%)	⬇️
doctr/models/recognition/sar/tensorflow.py	98.49% <0.00%> (-0.03%)	⬇️
doctr/models/recognition/zoo.py	100.00% <0.00%> (ø)
doctr/models/recognition/crnn/tensorflow.py	100.00% <0.00%> (ø)
doctr/models/core.py	94.61% <0.00%> (+0.76%)	⬆️

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[charlesmindee]

Thanks for the cut!