[MAINT] remove test install with python 2.7 workflow

[Remi-Gau]

Closes #3767

Changes proposed in this pull request:

• remove test install with python 2.7 workflow

[codecov]

Codecov Report

Merging #3768 (2fe496c) into main (b2562d6) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #3768   +/-   ##
=======================================
  Coverage   91.60%   91.60%           
=======================================
  Files         139      139           
  Lines       16591    16591           
  Branches     3244     3244           
=======================================
  Hits        15198    15198           
  Misses       1390     1390           
  Partials        3        3           

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[github-actions]

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[Remi-Gau]

OK no python 2.7 on GH: https://raw.githubusercontent.com/actions/python-versions/main/versions-manifest.json

[ymzayek]

I think it is safe to remove. Re #3767 (comment). I think if someone tries to do this and does so successfully we will hear about it because of other issues that will come up