[CI] Enable merge trigger unit test and accuracy test schedule job (#1345)

### What this PR does / why we need it?
- Enable merge trigger unit test and accuracy test schedule job
- Pin lm-eval==0.4.8 to resovle Qwen3 8B accuracy
### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
CI passed

Signed-off-by: Yikun Jiang <yikunkero@gmail.com>

.github/workflows/vllm_ascend_test.yaml

@@ -66,6 +66,8 @@ concurrency:
 
 jobs:
   lint:
+    # Only trigger lint on pull request
+    if: ${{ github.event_name == 'pull_request' }}
     runs-on: ubuntu-latest
     strategy:
       matrix:
@@ -131,7 +133,8 @@ jobs:
   ut:
     needs: [lint]
     name: unit test
-    if: ${{ needs.lint.result == 'success' }}
+    # only trigger e2e test on [pull request after lint passed] and [merged commit]
+    if: ${{ needs.lint.result == 'success' || github.event_name == 'push' }}
     runs-on: ubuntu-latest
     container:
       image: m.daocloud.io/quay.io/ascend/cann:8.1.rc1-910b-ubuntu22.04-py3.10
@@ -191,7 +194,8 @@ jobs:
 
   e2e:
     needs: [lint]
-    if: ${{ needs.lint.result == 'success' }}
+    # only trigger e2e test on pull request after lint passed
+    if: ${{ needs.lint.result == 'success' && github.event_name == 'pull_request' }}
     strategy:
       max-parallel: 2
       matrix: