Signed-off-by: Morten Linderud <foxboron@archlinux.org>

pathlib2 is never used, on python3 it uses pathlib and on python2 it vendors
pathlib2 for the build. We only care about the former.

Tests are bonkers, the builtin test runner reports pytest output but
unconditionally return success, make this explicit by the PKGBUILD pattern
|| echo "warning goes here"

Also the tests never ran due to passing pytest --boxed, but this needed
pytest-xdist and is now a no-op, because the behavior is now in pytest-forked
as --forked. Nevertheless, it makes for clearer errors if we get segfaults, so
reimplement this properly.

(sorry, I am really stupid)

Documentation isn't being generated as it requires the wxWidgets backend, whereas we are using GTK.

Documentation is not being generated as it is only avaliable if we are using the wxWidgets backend. We are using GTK.

Fixes FS#59880

add testsuite and ignore errors; the errors are the same on both python 3.6 and
python 3.7 so it is presumably okay on python 3.7

- python2-wxpython3: it provides the classic wxPython 3 for a long time 
for the existing applications.

- python-wxpython: it provides the new wxPython 4 for applications which 
want to port to Python 3.