[CI] Update UT CANN version to 8.5.0 for main branch (#6564)

### What this PR does / why we need it?
Update UT CANN version to 8.5.0

### Does this PR introduce _any_ user-facing change?
NA


- vLLM version: v0.15.0
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.15.0

---------

Signed-off-by: leo-pony <nengjunma@outlook.com>

.github/workflows/pr_test_light.yaml

@@ -92,7 +92,7 @@ jobs:
     with:
       vllm: ${{ matrix.vllm_version }}
       runner: linux-amd64-cpu-8-hk
-      image: quay.nju.edu.cn/ascend/cann:8.2.rc2-910b-ubuntu22.04-py3.11
+      image: quay.nju.edu.cn/ascend/cann:8.5.0-910b-ubuntu22.04-py3.11
       type: pr
 
   e2e-light: