ci(framework:skip) Make sure E2E template tests fail on ERROR (#3931)

.github/workflows/e2e.yml

@@ -213,7 +213,7 @@ jobs:
     needs: wheel
     strategy:
       matrix:
-        framework: ["numpy", "pytorch", "tensorflow", "huggingface", "jax", "sklearn"]
+        framework: ["numpy", "pytorch", "tensorflow", "jax", "sklearn"]
 
     name: Template / ${{ matrix.framework }}
 
@@ -234,12 +234,10 @@ jobs:
           flwr new tmp-${{ matrix.framework }} --framework ${{ matrix.framework }} --username gh_ci
           cd tmp-${{ matrix.framework }}
           pip install .
-      - name: Cache Datasets
-        uses: actions/cache@v4
-        with:
-          path: "~/.cache/huggingface/datasets"
-          key: ${{ matrix.framework }}-template-datasets
       - name: Run project
         run: |
           cd tmp-${{ matrix.framework }}
-          flwr run --run-config num-server-rounds=1
+          flwr run --run-config num-server-rounds=1 2>&1 | tee flwr_output.log 
+          if grep -q "ERROR" flwr_output.log; then
+            exit 1
+          fi