Add marks to remove the need for commenting/uncommenting pytest.ini

[IronEddy418]

Hey Jim! Really appreciate your work here on ML Testing - starting to learn about the MLOps world myself and there isn't much out there yet.

Regarding:

To run the tests in pipeline-tests or notebook-tests, uncomment them in pytest.ini and then re-run:

python3 -m pytest

You can use pytest marks to make this nicer for users of the repo (https://docs.pytest.org/en/7.1.x/how-to/mark.html, https://docs.pytest.org/en/7.1.x/example/markers.html)

Add this to your pytest.ini file:

markers =
    unit
    pipeline
    notebook

and then add an attribute to the unit tests like so:

@pytest.mark.unit or @pytest.mark.pipeline

and to then run tests you can do pytest -m unit or pytest -m pipeline. Saves having to edit files!