Revert "rank_filter.recipe/run_test.py: Run tests with `unittest`."
Revert "rank_filter.recipe/run_test.py: Run tests with `unittest`."

This reverts commit e65b8c39ac83841b8e582396bbff6b4dedb417cb.

DudLab/rank_filter,jakirkham/rank_filter,jakirkham/rank_filter,jakirkham/rank_filter,DudLab/rank_filter,nanshe-org/rank_filter,DudLab/rank_filter,nanshe-org/rank_filter,nanshe-org/rank_filter