ci: Add codecov to unit-tests.yml

Author: holtskinner

.github/workflows/unit-tests.yml

@@ -40,12 +40,13 @@ jobs:
       - name: Install dependencies
         run: uv sync --dev
 
-      - name: Run tests
-        run: uv run pytest
+      - name: Run tests with coverage
+        run: uv run pytest --cov --cov-report=xml
 
-      - name: Upload coverage report
-        uses: actions/upload-artifact@v4
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v4
         with:
-          name: coverage-report-${{ matrix.python-version }}
-          path: coverage.xml
-          if-no-files-found: ignore
+          file: ./coverage.xml
+          flags: python-${{ matrix.python-version }}
+          name: codecov-umbrella
+          fail_ci_if_error: true