Update python-app.yml

.github/workflows/python-app.yml

@@ -27,7 +27,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install flake8 pytest
-        if [ -f requirements.pip ]; then pip install -r requirements.pip; fi
+        if [ -f backend/requirements.pip ]; then pip install -r backend/requirements.pip; fi
     - name: Test with pytest
       run: |
         pytest -s backend/test/integration/test_create.py