chore(tox): Run with all cores

Author: effigies

tox.ini

@@ -52,7 +52,7 @@ uv_resolution =
 
 commands =
   python -c "import nitransforms; print(nitransforms.__version__)"
-  pytest --durations=20 --durations-min=1.0 --cov-report term-missing {posargs:-n 0}
+  pytest --durations=20 --durations-min=1.0 --cov-report term-missing {posargs:-n auto}
 
 [testenv:style]
 description = Check our style guide