When running tests, @pytest.mark.trio is not recognized

[PureTryOut]

I'm running the tests as I described here (PYTHONPATH="." pytest --pyargs pytest_trio), but it seems it doesn't recognize the marker correctly:

====================================================== ERRORS =======================================================
_____________________________ ERROR collecting pytest_trio/_tests/test_clock_fixture.py _____________________________
pytest_trio/_tests/test_clock_fixture.py:5: in <module>
    @pytest.mark.trio
/usr/lib/python3.8/site-packages/_pytest/mark/structures.py:513: in __getattr__
    warnings.warn(
E   pytest.PytestUnknownMarkWarning: Unknown pytest.mark.trio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
______________________________ ERROR collecting pytest_trio/_tests/test_contextvars.py ______________________________
pytest_trio/_tests/test_contextvars.py:35: in <module>
    ???
/usr/lib/python3.8/site-packages/_pytest/mark/structures.py:513: in __getattr__
    warnings.warn(
E   pytest.PytestUnknownMarkWarning: Unknown pytest.mark.trio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
_____________________________ ERROR collecting pytest_trio/_tests/test_fixture_names.py _____________________________
pytest_trio/_tests/test_fixture_names.py:11: in <module>
    ???
/usr/lib/python3.8/site-packages/_pytest/mark/structures.py:513: in __getattr__
    warnings.warn(
E   pytest.PytestUnknownMarkWarning: Unknown pytest.mark.trio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
____________________________ ERROR collecting pytest_trio/_tests/test_fixture_nursery.py ____________________________
pytest_trio/_tests/test_fixture_nursery.py:17: in <module>
    ???
/usr/lib/python3.8/site-packages/_pytest/mark/structures.py:513: in __getattr__
    warnings.warn(
E   pytest.PytestUnknownMarkWarning: Unknown pytest.mark.trio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
________________________ ERROR collecting pytest_trio/_tests/test_hypothesis_interaction.py _________________________
pytest_trio/_tests/test_hypothesis_interaction.py:19: in <module>
    @pytest.mark.trio
/usr/lib/python3.8/site-packages/_pytest/mark/structures.py:513: in __getattr__
    warnings.warn(
E   pytest.PytestUnknownMarkWarning: Unknown pytest.mark.trio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
_____________________________ ERROR collecting pytest_trio/_tests/test_sync_fixture.py ______________________________
pytest_trio/_tests/test_sync_fixture.py:9: in <module>
    ???
/usr/lib/python3.8/site-packages/_pytest/mark/structures.py:513: in __getattr__
    warnings.warn(
E   pytest.PytestUnknownMarkWarning: Unknown pytest.mark.trio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html

This is the latest git master in an attempt to get the Alpine Linux package working again now pytest has been updated to 6.0.x