Update tests.yml

Attempt to add code coverage to workflows

.github/workflows/tests.yml

@@ -1,6 +1,6 @@
 # This workflow installs and tests ipdw, currently only tests on ubuntu and Python 3.11
 
-name: Python application
+name: Build
 
 on:
   push:
@@ -35,7 +35,18 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install pytest
+        pip install pytest-cov
         pip install -r requirements.txt
     - name: Test with pytest
       run: |
-        pytest
+        pytest --cov=./ --cov-report=xml
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v3
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+        directory: ./coverage/reports/
+        env_vars: OS,PYTHON
+        files: ./coverage1.xml,./coverage2.xml,!./cache
+        flags: unittests
+        name: codecov-umbrella
+        verbose: true