Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/deploy.yml

@@ -14,7 +14,7 @@ jobs:
     name: Deploy to GitHub Pages
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
       - uses: actions/setup-node@v3
         with:
           node-version: 18

.github/workflows/npm.yml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Volans Website Build
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
       - name: Set up Node 18
         uses: actions/setup-node@v3
         with: