QT Admin. Upgrade to VueJS v3

[HalcyonJAC]

What's included?

Closes #39 Closes #26

• [x] Merge with main and fix conflicts (as the main branch has moved on since these changes were originally done).
• [x] Use vite instead of vue config.
• [x] Click through pages to ensure functionality works and fix ensuing bugs.
• [x] Get at least one test running using vitest.

How to test?

Run qt-admin locally (npm run serve) and test the following functionalities:

• Sign in

• Folder

  • Add a folder
  • Edit a folder
  • Delete a folder

• Qualifying tests

  • Create new
    • Scenario test
    • Critical analysis
    • Situational judgement
  • Create new from clipboard
  • Open tests
  • Close & score
  • Create mop up test

• Qualifying test responses

  • Mark as completed
  • Reset
  • Reasonable Adjustments