Bump checkout version gh actions (#2573)

* upgrade checkout v6 gh actions

* changed personal token to gh token

Author: DMarinhoCodacy

.github/workflows/mkdocs.yml

@@ -96,7 +96,7 @@ jobs:
         uses: peaceiris/actions-gh-pages@v4
         if: github.ref == 'refs/heads/master'
         with:
-          personal_token: ${{ secrets.DEPLOYMENT_PERSONAL_ACCESS_TOKEN }}
+          personal_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./site
           destination_dir: ./
           keep_files: true