Switch from coveralls to codecov

Author: jan-janssen

.github/workflows/pipeline.yml

@@ -122,8 +122,10 @@ jobs:
         coverage run
         coverage report
         coverage xml
-    - name: Coveralls
-      uses: coverallsapp/github-action@v2
+    - name: Upload coverage reports to Codecov
+      uses: codecov/codecov-action@v5
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
 
   notebooks:
     needs: [black]