Update python-app.yml

more lint checker stuff

.github/workflows/python-app.yml

@@ -22,7 +22,6 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install flake8
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
     - name: Test with Unittest
       run: |