add testing on py3

Author: Alonreznik

.github/workflows/run_uts_on_prs.yml

@@ -28,6 +28,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install -r test-requirements.txt
+        python setup.py install
     - name: Test with pytest
       run: |
         pytest tests --durations=5 --durations-min=180.0 -W ignore::DeprecationWarning