Prevent pushing commits if the tests are unsuccessful

.github/workflows/python-app.yml

@@ -1,7 +1,5 @@
-# This workflow will install Python dependencies, run tests and lint with a single version of Python
-# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-python
+name: SimulationSandBox CI
 
-name: SimulationSandBox 
 on:
   push:
     branches: [ "main" ]
@@ -18,18 +16,26 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+
     - name: Set up Python 3.10
       uses: actions/setup-python@v3
       with:
         python-version: "3.10"
+
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+
     - name: Reformat with black 
       run: |
         black . --diff --color 
         black .
+
     - name: Test with pytest
       run: |
         pytest
+
+    - name: Prevent push on test failure
+      if: failure()
+      run: exit 1