Remove ~"pipeline:mr-approved" from MR when there are no approvals
Context
When an MR is first approved, we apply the ~"pipeline:mr-approved" label.
This label isn't removed anymore by triage-ops, even when the merge request approvals are removed.
Goal
Remove the pipeline:mr-approved label as soon as we see that the Merge Request doesn't have approvals anymore (e.g. due to a code change).