New review comment by eli-schwartz on void-packages repository

https://github.com/void-linux/void-packages/pull/37132#discussion_r1161871512

Comment:
> if there are no tests, they usually don't fail, so we don't have to disable them

Incorrect, the python3-module build style does this all the time, because it attempts to run `python3 setup.py test` regardless of whether tests exist. This command will:
- depend on all runtime dependencies, or attempt to install local copies of them with pip, but NOT all "extras" (optional) dependencies
- then import all source files (including the ones that have optional dependencies, which are not otherwise mentioned in the template since xbps does not support optional dependencies)
- then detect that there are zero tests, and not run them

And setuptools upstream has deprecated `setup.py test`, so any packages that actually used it (which was relatively uncommon, as people tend to prefer pytest or nose or whatever) have been busily porting away from it.

Incidentally, this: https://github.com/void-linux/void-packages/blob/0657a8bea7e6d89cff327e31949b5eebcb883952/common/build-style/python3-module.sh#L21-L23

is logically broken, because it is fallaciously incorrect to print a warning that "setup.py doesn't define a test command". That's not the role of setup.py to do -- the test command is defined globally in setuptools itself regardless of what a setup.py file does (a setup.py file can override the builtin one, the same way it can override the builtin "build_py" or "install" commands).