GitLab statuses are not published for new source revisions when the evaluation does not change

[hacker1024]

Describe the bug

When a GitLab repository input's revision changes, and Hydra re-evaluates the jobset but nothing new affects the result, then no new evaluation is actually created and no new jobs are ran.

This means that GitLab statuses for the new revision are not published.

To Reproduce
Steps to reproduce the behavior:

1. Add a GitLab source input with the status plugin configured
2. Make an arbitrary change that does not affect evaluation
3. Note that no new statuses are published

Expected behavior

When a new source revision is published, Hydra's GitLab status plugin should publish statuses for that revision even if nothing significant has changed.