Add step to display coverage directory structure in CI

.github/workflows/ci.yml

@@ -358,6 +358,8 @@ jobs:
         with:
           pattern: frontend-coverage-*
           path: ./coverage/
+      - name: Display structure of downloaded coverage
+        run: ls -R ./coverage/
       - name: Set up Python
         uses: actions/setup-python@v5
         with: