Enable unit tests in GitHub Actions

.github/workflows/fly.yml

@@ -4,6 +4,24 @@ on:
     branches:
       - main
 jobs:
+  pre-deploy-test:
+    name: Unit tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade 
+          pip install poetry
+          poetry install --no-interaction --no-ansi --dev
+      - 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
+
   deploy:
     name: Deploy app
     runs-on: ubuntu-latest