This change overrides a check added in Ubuntu 24.04+ that prevents
mixing Python packages installed through apt and through pip. This
allows to install the necessary Python package for TC which isn't
available as Debian package. This change allows builds on Ubuntu 24.04
based TC agents.
This change rename the test files for Linux according to the discussion
at the Keyman conference in November 2024.
Python is pretty opinionated about the naming of files, so we have to
use `*_tests.py` as test filename instead of the usual `*.tests.py`.
