[BACKEND] Neaten and tidy all the route tests

[jeffplays2005]

Is your feature request related to a problem? Please describe. After the migration of a single routes.test.ts file to individual route tests, it's perhaps better to just look over them and tidy up any messy route tests. Makes it easier to debug any faulty route tests and also just makes backend perhaps faster...

Describe the solution you'd like Go through every route test and change them accordingly

BEFORE MERGING

• [ ] Integration test written for services
• [ ] Schemas annotated if adding new models
• [ ] Code generation run (hint: yarn workspace server tsoa spec-and-routes)
• [ ] Appropriate mocks created where possible
• [ ] PR Reviewed (For non-trivial changes)
• [ ] Changes tested after rebasing on master or merging in master (hint: git fetch origin master:master, then git rebase master or git merge master)
• [ ] All required PR checks passing