Update actions/checkout action to v7

Author: renovate[bot]

.github/workflows/github-pages.yml

@@ -39,7 +39,7 @@ jobs:
       - name: Install Dart Sass
         run: sudo snap install dart-sass
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v7
         with:
           submodules: recursive
       - name: Setup Pages