Use tox in GitHub Action

Author: oschwald

.github/workflows/test.yml

@@ -28,6 +28,7 @@ jobs:
         run: |
               python -m pip install --upgrade pip
               pip install -e git+https://github.com/maxmind/GeoIP2-python#egg=geoip2
+              pip install tox tox-gh-actions
 
-      - name: Test
-        run: python setup.py test
+      - name: Test with tox
+        run: tox