♻️ refactor tests which require database objects

[bunop]

Is your feature request related to a problem? Please describe.
Tests should be refactored in order to initialize data from fixtures. This will make easier the testing processes, even in most difficult requirement setup

Describe the solution you'd like
Database relates tests should start by fixtures upload, and requirements must be managed by uploading json objects

Describe alternatives you've considered
Test could remain like this, however it seems difficult to proper setup certain tests

Additional context
See tests in SMARTER-backend and take inspirations by django tests