docs: update test command

DenverCoder1 · web-flow · commit 23f25ddaae51 · 2021-08-15T15:12:13.000+03:00
diff --git a/README.md b/README.md
@@ -195,7 +195,7 @@ All parameters are optional.
 
 To run tests (pytest)
 
-``python setup.py test``
+``tox``
 
 To lint (flake8):
 
