TST/CI: Reduce number of unnecessary numba tests in groupby ops
- [x] closes #42236
- [x] tests added / passed
- [x] Ensure all linting tests pass, see [here](https://pandas.pydata.org/pandas-docs/dev/development/contributing.html#code-standards) for how to run them

Limiting the numba `engine_kwargs` parameterization for groupby tests similar to #42024

cc @mzeitlin11 