Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
This changes ProcessCommitWorker so that it takes a Hash containing commit data instead of a commit SHA. This means the worker doesn't have to access Git just to process a commit message (and other data it may use). This in turn should solve the problem of ending up with 15 000-something jobs in the process_commit queue that take forever to process.