[tests] Add categories for unit tests #423
Description
Is your request related to a problem? Please describe.
We could add a category facet to the unit test blocks, it would make it possible to arrange them in semantically closer groups in the same way that we already do for experiment parameters which makes them more easily readable to the user.
Describe the improvement you'd like
A new facet to add a category to unit tests, and the corresponding grouping done in the test view
Additional context
It could help build and maintain unit tests more easily