Only add coverage comment to pull requests

.github/workflows/python-package.yml

@@ -43,6 +43,7 @@ jobs:
       run: pytest --junitxml=pytest.xml --cov-report=term-missing:skip-covered --cov=mvt tests/ | tee pytest-coverage.txt
     - name: Pytest coverage comment
       uses: MishaKav/pytest-coverage-comment@main
+      if: github.event_name == 'pull_request'
       with:
         pytest-coverage-path: ./pytest-coverage.txt
         junitxml-path: ./pytest.xml