[CI] Make coverage generate pull request comment instead of blocking validation

[hugsy]

Description/Motivation/Screenshots

Move coverage to separate job on CI, to only send coverage results as comment to the PR (instead of failing it if lower).

This will give us a per-commit improvement for the PR. Based on that info, we can then decide to approve or reject if the drop is too high. This is less aggressive that failing the CI tests.

Against which architecture was this tested ?

N/A (CI only)

Checklist

• My PR was done against the dev branch, not main.
• My code follows the code style of this project.
• My change includes a change to the documentation, if required.
• If my change adds new code, adequate tests have been added.
• I have read and agree to the CONTRIBUTING document.

[github-actions]

🤖 Coverage Update

• Commit: e5ff08e
• Current Coverage: 71.3331%
• New Coverage: 71.3331%
• Diff: 0.0

[github-actions]

🤖 Coverage Update

• Commit: 09273b9
• Current Coverage: 71.3331%
• New Coverage: 71.3331%
• Diff: 0.0