Tests are failing (I'm on fixing CI)

[raven-wing]

I'm currently working to make python-mapnik work on CI again (moving to github actions). Task is to build package that will be hosted in pypi, but tests are failing... You can see PR here

As you can see - it's green, yet tests, are failing. So:

1. tests should be fixed,
2. tests running scripts should be fixed to return nonzero code.

[raven-wing]

My latest changes are even producing whl wich could be not so far from being able to do pip install mapnik. :)

Though we need working tests.