Stop using deprecated distutils.version.LooseVersion in tests.

Stop using deprecated distutils.version.LooseVersion in tests.

I was waiting *half a decade* for this to get resolved in a less than
insane way, but NOPE. Instead of using builtin functionality for such a
basic operation as version comparison (heck, even CMake has that
builtin!!) we're now instructed to PIP INSTALL PACKAGING. Where did the
"batteries included" spirit go? Why is everything increasingly
overengineered? Why can't a project stay in place for a few years, WHY
DO I HAVE TO ADAPT TO MEANINGLESS CHANGES ALL THE TIME?!