ci: pin vtk-osmesa version

[SMoraisAnsys]

Description

As title says. Avoid using non pinned version of vtk-osmesa to prevent supply chain attack.

Issue linked

None

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 88.90%. Comparing base (9e896b0) to head (766bdba).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #675      +/-   ##
==========================================
- Coverage   88.91%   88.90%   -0.01%     
==========================================
  Files          39       39              
  Lines        5618     5617       -1     
==========================================
- Hits         4995     4994       -1     
  Misses        623      623              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.