After Action Review of #437

See issue - https://github.com/galaxyproject/planemo/issues/437 the bug is too serious and was open for too long. There should have been testing to catch it and the fix should have come out sooner.
- [ ] Consider updating release process to include release branches - this might have made it easier to perform a non-master fix or an existing point release.
- [ ] Update TS testing so mock shed's users API endpoint mirrors real shed's.
- [ ] Add extended tool shed tests to test planemo against an actual tool shed when longer tests run. Mock real tool shed with multiple users.