Merge branch 'tests' of https://github.com/SupervisedStylometry/Super…

…Styl into tests

.github/workflows/python-package.yml

@@ -26,6 +26,7 @@ jobs:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies
       run: |
+        sudo apt install python3-dev
         python -m pip install --upgrade pip
         python -m pip install flake8 pytest
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi