Add isort to tox checkqa

Author: hramezani

tox.ini

@@ -54,10 +54,12 @@ extras =
 deps =
     flake8
     mypy==0.910
+    isort
 commands =
     flake8 --version
     flake8 --statistics {posargs:pytest_django pytest_django_test tests}
     mypy {posargs:pytest_django pytest_django_test tests}
+    isort --check-only --diff pytest_django pytest_django_test tests
 
 [testenv:doc8]
 extras =