Is your feature request related to a problem? Please describe.

I would like to mark new tests I develope with a custom mark, so I can select them with the pytest command. This results in the following error however: pytest.PytestUnknownMarkWarning: Unknown pytest.mark.XXX- is this a typo? You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html

Describe the solution you'd like

I would like to have a custom mark added to the conf file so I can use it.

Describe alternatives you've considered

I can alternatively use -k to select the tests I want but that is more cumbersome in my opinion.