Investigate async race condition in MergeRequest::RefreshService
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We identified a race condition in `MergeRequest::RefreshService` that we suspect is due to an async process OR multiple calls to the service firing. We patched the immediate issue by adding a 10-second delay to the worker to allow for whatever the issue is to clear, but this is more of a bandage than a solution.
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/96933#note_1097492625
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