Rework Githuh Actions into a single workflow

[bouthilx]

There is no need to duplicate the workflows and this lead to hard to
maintain duplicates.

[codecov]

Codecov Report

Merging #461 (9d5b3db) into develop (19e4df8) will decrease coverage by 0.02%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop     #461      +/-   ##
===========================================
- Coverage    49.33%   49.31%   -0.03%     
===========================================
  Files           81       81              
  Lines        13922    13922              
  Branches       345      345              
===========================================
- Hits          6869     6865       -4     
- Misses        7036     7038       +2     
- Partials        17       19       +2     

Flag	Coverage Δ
backward	97.81% <ø> (?)
unittests	48.80% <ø> (-0.50%)	⬇️

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Impacted Files	Coverage Δ
tests/unittests/algo/test_evolution_es.py	89.44% <0.00%> (-2.49%)	⬇️

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