chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/build.yaml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ubuntu-latest
     name: 'Build and Test'
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
         with:

.github/workflows/deploy.yaml

@@ -30,7 +30,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: Setup Pages
         uses: actions/configure-pages@v5
       - name: Setup Ruby