updated yml to add auto tests

.github/workflows/python-app.yml

@@ -36,4 +36,4 @@ jobs:
         flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
     - name: Test with pytest
       run: |
-        pytest
+        pytest calculator_test.py --doctest-modules --junitxml=junit/test-results.xml --cov=com --cov-report=xml --cov-report=html