chore: rework logic around vtk-osmesa

[SMoraisAnsys]

Description

Updating the logic around the use of vtk on CI / doc build to leverage vtk's feature of defining an OpenGL context backend. This should avoid any issue that happens from time to time when trying to retrieve wheels from VTK's GitLab registry.

Issue linked

None yet

Checklist

• I have tested my changes locally.
• I have added necessary documentation or updated existing documentation.
• I have followed the coding style guidelines of this project.
• I have added appropriate tests (unit, integration, system).
• I have reviewed my changes before submitting this pull request.
• I have linked the issue or issues that are solved by the PR if any.
• I have assigned this PR to myself.
• I have made sure that the title of my PR follows Conventional commits style (e.g. feat: add optical property)
• I have agreed with the Contributor License Agreement (CLA).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.52%. Comparing base (07f1a7c) to head (269a909).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #774   +/-   ##
=======================================
  Coverage   87.52%   87.52%           
=======================================
  Files          40       40           
  Lines        5762     5762           
=======================================
  Hits         5043     5043           
  Misses        719      719           

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