Automating `needs-rebase` label

Hi all, After automating the per-component labelling in Pull Requests, this next PR <https://github.com/ceph/ceph/pull/38548> is adding automation to the `needs-rebase` label with the help of this Github Action <https://github.com/marketplace/actions/label-conflicting-pull-requests>. When the base branch (e.g.: master) of a PR is updated and the PR merge results in conflicts: - `needs-rebase` label will automatically be added. - `ready-to-merge` label will be removed - The following comment will be added: "This pull request can no longer be automatically merged: a rebase is needed and changes have to be manually resolved". When the PR is rebased, conflict solved and re-pushed: - The `needs-rebase` label will be automatically removed (`ready-to-merge` label won't be added back though) Kind Regards, Ernesto Puerta He / Him / His Senior Software Engineer, Ceph Red Hat <https://www.redhat.com/> <https://www.redhat.com/>