[Build] Fix GPU builds (#1453)

The latest PyTorch disagrees with the NVIDIA driver version on the GitHub runners. For now, put an upper bound on PyTorch, but this isn't a long term solution.

Author: riedgar-ms

.github/workflows/call_gpu_tests.yml

@@ -63,8 +63,11 @@ jobs:
         run: |
           nvidia-smi
           sudo apt-get --yes update
-          sudo apt-get --yes install cuda-toolkit-12.6
-          echo "/usr/local/cuda-12.6/bin" >> $GITHUB_PATH
+          sudo apt-get --yes install cuda-toolkit-12.8
+          echo "/usr/local/cuda-12.8/bin" >> $GITHUB_PATH
+      - name: Install older pytorch (CUDA compatibility)
+        run: |
+          pip install "torch<2.11"
       - name: Install other packages
         shell: bash
         run: |