add pytest-xdist

tox.ini

@@ -10,12 +10,13 @@ concurrency = multiprocessing,thread
 
 [testenv]
 deps =
+    pytest-xdist
     pytest-cov
     flake8
     -r requirements.txt
 
 commands =
     coverage erase
-    pytest --cov brian_dashboard_manager --cov-fail-under=75 --cov-report html --cov-report xml --cov-report term -p no:checkdocs
+    pytest -n auto --cov brian_dashboard_manager --cov-fail-under=75 --cov-report html --cov-report xml --cov-report term -p no:checkdocs
     flake8
     sphinx-build -M html docs/source docs/build