Update ci-pipeline.yml

.github/workflows/ci-pipeline.yml

@@ -63,6 +63,7 @@ jobs:
           python-version: 3.9
       - name: Install dependencies
         run: |
+          pip install torch torchvision --index-url https://download.pytorch.org/whl/cpu
           pip install -r docs/requirements.txt
           pip install .
       - name: Build documentation