[CI] Nightly tests use releases/v0.13.0 (#6355)

### What this PR does / why we need it?
The pre-requirement pr is
https://github.com/vllm-project/vllm-ascend/pull/6353, this patch aims
to transfer nightly tests to `releases/v0.13.0`, what we need to do is
just use the branch built image for nightly

- vLLM version: v0.14.1
- vLLM main:
dc917cceb8

---------

Signed-off-by: wangli <wangli858794774@gmail.com>

.github/Dockerfile.nightly.a2

@@ -15,7 +15,7 @@
 # This file is a part of the vllm-ascend project.
 #
 
-FROM quay.io/ascend/vllm-ascend:main
+FROM quay.io/ascend/vllm-ascend:v0.13.0-dev
 
 ARG PIP_INDEX_URL="https://mirrors.tuna.tsinghua.edu.cn/pypi/web/simple"
 ARG AIS_BENCH_TAG="v3.0-20250930-master"

.github/Dockerfile.nightly.a3

@@ -15,7 +15,7 @@
 # This file is a part of the vllm-ascend project.
 #
 
-FROM quay.io/ascend/vllm-ascend:main-a3
+FROM quay.io/ascend/vllm-ascend:v0.13.0-dev-a3
 
 ARG PIP_INDEX_URL="https://mirrors.tuna.tsinghua.edu.cn/pypi/web/simple"
 ARG AIS_BENCH_TAG="v3.0-20250930-master"

.github/workflows/schedule_nightly_image_build.yaml

@@ -22,6 +22,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+          ref: releases/v0.13.0
 
       - name: Show build target
         run: |