fix(backend-gitlab): skip creating a CI pipeline when rebasing merge request (#4802)
fix(backend-gitlab): skip creating a CI pipeline when rebasing merge request (#4802)

Fixes #4786; see further https://docs.gitlab.com/ee/api/merge_requests.html#rebase-a-merge-request
netlify/netlify-cms,netlify/netlify-cms,netlify/netlify-cms,netlify/netlify-cms