ci(workflow): 🚀 升级 GitHub Actions 工作流依赖版本

* 将 `actions/checkout` 从 v3 升级至 v6。
* 将 `actions/setup-python` 从 v4 升级至 v6，并将 Python 版本从 `3.7` 升级至 `3.12`。
* 将 `actions/cache` 从 v3 升级至 v5。

Author: hex-ci

.github/workflows/build.yml

@@ -11,15 +11,15 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v6
       with:
         submodules: recursive
         fetch-depth: 10
 
     - name: Install Python
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v6
       with:
-        python-version: '3.7'
+        python-version: '3.12'
 
     - name: Install OS dependencies
       run: |
@@ -33,7 +33,7 @@ jobs:
         echo "dir=$(pip cache dir)" >> $GITHUB_OUTPUT
 
     - name: Cache dependencies
-      uses: actions/cache@v3
+      uses: actions/cache@v5
       with:
         path: ${{ steps.pip-cache.outputs.dir }}
         key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
@@ -50,7 +50,7 @@ jobs:
         make latexpdf
 
     - name: Checkout gh-pages
-      uses: actions/checkout@v3
+      uses: actions/checkout@v6
       with:
         repository: ${{ github.repository }}
         ref: gh-pages