Server fix for #20397. (I incorrectly added that `last_enrolled_at = NOW()` on the first iOS/iPadOS support PR.) - [X] Changes file added for user-visible changes in `changes/`, `orbit/changes/` or `ee/fleetd-chrome/changes`. See [Changes files](https://fleetdm.com/docs/contributing/committing-changes#changes-files) for more information. - [x] Added/updated tests. - [ ] Manual QA for all new/changed functionality.