Updated GH Action to checkout/v4 to fix warning https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

Author: dfreniche

.github/workflows/deploy.yml

@@ -12,7 +12,7 @@ jobs:
     name: Deploy to GitHub Pages
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - uses: actions/setup-node@v3
         with:
           node-version: 20