Modify github flake8 action (#154)

Author: chrisruk

.github/workflows/python-app.yml

@@ -34,5 +34,3 @@ jobs:
         flake8 . --version
         # stop the build if there are Python syntax errors or undefined names
         flake8 . --count --show-source --statistics
-        # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
-        flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics