reverse the amd ci test back to 1200s and split the 8-gpu deepseek job into two. (#11238)

Co-authored-by: root <root@smci350-zts-gtu-e17-15.zts-gtu.dcgpu>

.github/workflows/pr-test-amd.yml

@@ -296,6 +296,7 @@ jobs:
       fail-fast: false
       matrix:
         runner: [linux-mi300-gpu-8]
+        part: [0, 1]
     runs-on: ${{matrix.runner}}
     steps:
       - name: Checkout code
@@ -315,7 +316,7 @@ jobs:
       - name: Run test
         timeout-minutes: 60
         run: |
-          bash scripts/ci/amd_ci_exec.sh python3 run_suite.py --suite per-commit-8-gpu-amd --timeout-per-file 3600
+          bash scripts/ci/amd_ci_exec.sh python3 run_suite.py --suite per-commit-8-gpu-amd --auto-partition-id ${{ matrix.part }} --auto-partition-size 2 --timeout-per-file 3600
 
   unit-test-sgl-kernel-amd:
     if: github.event_name != 'pull_request' || contains(github.event.pull_request.labels.*.name, 'run-ci')