Limiting the python upper version to 3.11

[germa89]

Until pyvista (and hence vtk) supports python 3.12. We are stuck on 3.11.

Close #2427

Collecting vtk>=9.0.0 (from ansys-mapdl-core==0.68.dev0)
  Using cached vtk-9.2.6-cp311-cp311-macosx_11_0_arm64.whl (58.9 MB)
INFO: pip is looking at multiple versions of ansys-mapdl-core to determine which version is compatible with other requirements. This could take a while.
ERROR: Package 'ansys-mapdl-core' requires a different Python: 3.11.6 not in '<3.11.0,>=3.8.1'

[notice] A new release of pip is available: 23.2.1 -> 23.3.1
[notice] To update, run: pip install --upgrade pip
(tempvenv) german.ayuso@Ansys-WYN9VF7KGG pymapdl % 

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[codecov]

Codecov Report

Merging #2469 (bd6f29c) into main (03c9db3) will increase coverage by 0.27%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #2469      +/-   ##
==========================================
+ Coverage   83.51%   83.78%   +0.27%     
==========================================
  Files          44       44              
  Lines        8660     8660              
==========================================
+ Hits         7232     7256      +24     
+ Misses       1428     1404      -24     

[RobPasMue]

By the way, why >=3.8.1 and not just 3.8?

[germa89]

By the way, why >=3.8.1 and not just 3.8?

Because I miss read a comment in stackoverflow so I thought I had to specify the 3 digits version. But it is not needed indeed.