[META] - Nebari testing suite enhancements

[iameskild]

### Tasks
- [ ] https://github.com/nebari-dev/nebari/issues/1956
- [ ] https://github.com/nebari-dev/nebari/issues/2337
- [ ] https://github.com/nebari-dev/nebari/issues/2338

### Unit tests
- [ ] https://github.com/nebari-dev/nebari/issues/2339
- [ ] https://github.com/nebari-dev/nebari/issues/1978
- [ ] https://github.com/nebari-dev/nebari/issues/1944

### Playwright integration tests
- [ ] https://github.com/nebari-dev/nebari/issues/1971
- [ ] https://github.com/nebari-dev/nebari/issues/2020
- [ ] https://github.com/nebari-dev/nebari/issues/2340
- [ ] https://github.com/nebari-dev/nebari/issues/2341
- [ ] https://github.com/nebari-dev/nebari/issues/2342