[CI] optimize lint term (#5986)

### What this PR does / why we need it?
This patch purpose to optimize the lint check term. The main idea is to
reduce unnecessary installation time.
1. The installation of vllm is not must, only append the path of vllm
src to the `PATHONPATH` is effective
2. This installation of `requirements-dev.txt` is not must, we have a
pre-built image `quay.io/ascend-ci/vllm-ascend:lint` with all the
requirements installed in advance.
**NOTE**: the conditions for triggering image builds are: 1).Daily
scheduled build; 2) Build when requirements are modified; 3) Manual
build. This ensures that the dependencies in our image are up-to-date to
the greatest extent possible.
3. The `mypy` was separated from the `pre-commit` hook for performance
reasons; we found that integrating `mypy` into the `pre-commit` hook
resulted in poor performance.
4. Reduce the CPU core consumption from 16 -> 8

### Does this PR introduce _any_ user-facing change?
The end-to-end lint time was optimized from 20min/per PR to 8min/per PR
### How was this patch tested?

- vLLM version: v0.13.0
- vLLM main:
2c24bc6996

---------

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

.github/workflows/_pre_commit.yml

@@ -12,19 +12,16 @@ permissions:
 
 jobs:
   pre-commit:
-    runs-on: linux-amd64-cpu-16-hk
+    runs-on: linux-amd64-cpu-8-hk
     container:
       # Build it from https://github.com/nv-action/vllm-benchmarks/blob/main/Dockerfile
-      image: swr.cn-southwest-2.myhuaweicloud.com/base_image/ascend-ci/vllm-ascend:nightly-cpu
-    env:
-      GOPROXY: https://goproxy.io,direct
-      GITHUB_WORKSPACE: /__w/vllm-ascend/vllm-ascend
+      image: quay.io/ascend-ci/vllm-ascend:lint
     steps:
     - name: Checkout vllm-project/vllm-ascend repo
       uses: actions/checkout@v6
 
     # With problem matchers in a container, the output of $GITHUB_WORKSPACE and ${{ github.workspace }} are different.
-    # So we will just copy it into the path ${{ github.workspace }}. see https://github.com/actions/runner/issues/2058
+    # So we will just copy it into a temp path. see https://github.com/actions/runner/issues/2058
     - name: cp problem matchers
       run: |
         cp .github/workflows/matchers/actionlint.json "$RUNNER_TEMP/actionlint.json"
@@ -41,14 +38,21 @@ jobs:
         repository: vllm-project/vllm
         path: ./vllm-empty
         ref: ${{ inputs.vllm }}
-    - name: Install vllm
-      working-directory: vllm-empty
-      run: |
-        VLLM_TARGET_DEVICE=empty python3 -m pip install . --extra-index https://download.pytorch.org/whl/cpu/
-    - name: Install vllm-ascend dev
+    - uses: dorny/paths-filter@v3
+      id: filter
+      with:
+        filters: |
+          lint_tracker:
+            - 'requirements.txt'
+            - 'requirements-dev.txt'
+            - 'requirements-lint.txt'
+
+    - name: Install vllm-ascend dev (conditional)
+      if: steps.filter.outputs.lint_tracker == 'true'
       run: |
         git config --global --add safe.directory /__w/vllm-ascend/vllm-ascend
         pip install -r requirements-dev.txt --extra-index-url https://download.pytorch.org/whl/cpu
+
     - name: Run pre-commit
       env:
         PRE_COMMIT_COLOR: always
@@ -56,4 +60,17 @@ jobs:
         TERM: xterm-256color
         SHELLCHECK_OPTS: "--exclude=SC2046,SC2006,SC2086" # Exclude SC2046, SC2006, SC2086 for actionlint
       run: |
+        git config --global --add safe.directory /__w/vllm-ascend/vllm-ascend
         pre-commit run --all-files --hook-stage manual --show-diff-on-failure
+    - name: Run mypy
+      run: |
+        PYTHONPATH="$PYTHONPATH:$(pwd)/vllm-empty"
+        export PYTHONPATH
+        git config --global --add safe.directory /__w/vllm-ascend/vllm-ascend
+        # Run mypy for Python 3.10, 3.11, 3.12 manually
+        # Note: We are now separating mypy from pre-commit hooks for performance reasons.
+        for python_version in "3.10" "3.11" "3.12"; do
+          echo "============================"
+          tools/mypy.sh 1 "$python_version"
+          echo "============================"
+        done