Those tests are here mostsly to ensure ID name management is working as
expected (the code ensuring we never have two ilocal data-blocks of the
same type with the same name in a .blend file).
Note: Currently fails in some cases, fixes are incoming.
Note: Ideally this would be in C, but we already have too many tests
linking the whole Blender and its libraries, this is becoming a real
pain to link debug + ASAN + tests build these days... So until we find a
better way to handle those dependencies, sticking to simple python
scripts.