ci: verify that frontend still builds

An update to the react typings were automerged because the passed the CI.
In reality they broke the frontend build. Addings this job will make
sure that the frontend always builds after updated dependencies.

.github/workflows/ci.yaml

@@ -58,6 +58,9 @@ jobs:
 
       - run: npm run lint:frontend
 
+      - run: npm run build
+        working-directory: frontend
+
       - name: Archive code coverage results
         uses: actions/upload-artifact@v3
         with: