This commit includes squashed changes from
https://codeberg.org/guix/guix/pulls/7220 and
https://codeberg.org/guix/guix/pulls/7338.
* gnu/packages/aux-files/python/pytest_guix.py: New file.
* Makefile.am: Record it.
* guix/build/pyproject-build-system.scm (check): Preload pytest_guix
plugin when available.
* guix/build-system/pyproject.scm (default-pytest-guix-plugin): New
package, generated from pytest_guix.py.
(lower): Add python-pytest-guix argument, and inject it if
python-pytest is in the native-inputs.
Change-Id: I13263b461e9962aad340347657b9c9685db63927
Signed-off-by: Sharlatan Hellseher <sharlatanus@gmail.com>
