[CI] Add git safe repo (#7501)

### What this PR does / why we need it?
Add git safe repo to avoid dubious ownership error

- vLLM version: v0.17.0
- vLLM main:
8b6325758c
---------
Signed-off-by: wangli <wangli858794774@gmail.com>

.github/workflows/_e2e_nightly_single_node_models.yaml

@@ -84,6 +84,7 @@ jobs:
           pip config set global.index-url https://mirrors.tuna.tsinghua.edu.cn/pypi/web/simple
           apt-get update -y
           apt install git -y
+          git config --global --add safe.directory /__w/vllm-ascend/vllm-ascend
           git config --global url."https://gh-proxy.test.osinfra.cn/https://github.com/".insteadOf https://github.com/
 
       - name: Checkout vllm-project/vllm-ascend repo