fix: pr actions

[SalimKayal]

Improve CI/CD for release process

Description:
This PR introduces enhancements to our CI/CD pipeline, specifically focusing on the release process and branch protection.

Key changes include:

• Triggering tests for release PRs: Modified the test workflow to be triggered by repository_dispatch events, allowing tests to run automatically for release-related pull requests, which helps satisfy branch protection rules. This ensures that release branches are always thoroughly tested before merging.
• Force tag rewriting: Updated the update-versions workflow to use git push --force --tags when pushing release tags. This addresses the fact that the release process rewrites the tag for the new file versions.

These changes aim to make our release process more robust and compliant with branch protection policies.

[rokroskar]

Thanks for working on this @SalimKayal! I think a better solution might be to not trigger these workflows on tags but instead make them manually triggered? For example, like we do here: https://github.com/SwissDataScienceCenter/renku/blob/master/.github/workflows/create-release-branch.yml#L3-L13

That way we don't need the force push and tag rewriting, which are a bit hacky maybe?

[SalimKayal]

yep that's better indeed. do we need the target branch or should we simply use main's head?

[rokroskar]

oh probably don't need the target branch, it will always be main