deps defined in setup.py, so use this to install

Author: vonHartz

.github/workflows/gh-test.yml

@@ -24,7 +24,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install flake8 pytest pytest-cov
-        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi\
+        pip install -e .[extras]
     - name: Lint with flake8
       run: |
         # stop the build if there are Python syntax errors or undefined names