Update python-package.yml to point to correct tests file

.github/workflows/python-package.yml

@@ -31,4 +31,4 @@ jobs:
     - name: Test with pytest
       run: |
         pip install pytest pytest-cov
-        pytest tests.py --doctest-modules --junitxml=junit/test-results.xml --cov=com --cov-report=xml --cov-report=html
+        pytest ./tests/ --doctest-modules --junitxml=junit/test-results.xml --cov=com --cov-report=xml --cov-report=html