Comma cleanup for #35925
- [x] pandas/tests/generic/test_finalize.py
- [x] pandas/tests/generic/test_to_xarray.py
- [x] pandas/tests/groupby/aggregate/test_numba.py
- [x] pandas/tests/groupby/test_apply.py
- [x] pandas/tests/groupby/test_categorical.py
- [x] pandas/tests/groupby/test_groupby.py
- [x] pandas/tests/groupby/test_groupby_dropna.py
- [x] pandas/tests/groupby/test_groupby_subclass.py

Thanks @JonathanShrek 