WIP: backend for removing approvals
In tandem with !906 (closed), will close #894 (closed), #1262 (closed), #1287 (closed), #1288 (closed).
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
In tandem with !906 (closed), will close #894 (closed), #1262 (closed), #1287 (closed), #1288 (closed).