Run Python tests in GitHub actions

Author: mwarzybok-sumoheavy

.github/workflows/build.yml

@@ -29,12 +29,12 @@ jobs:
       - name: Install dependencies
         run: |
           pipenv install --dev
+          pipenv run pip3 install typing-extensions
       - name: Run code formatter
         run: pipenv run black src/
       - name: Run static analysis
         run: |
           pipenv run mypy --install-types --non-interactive src/
           pipenv run mypy -p src
       - name: Run unit tests
-        run: pipenv run pytest -vv -s -m unit
-
+        run: pipenv run pytest -vv -s -m unit