Update publishing token used for gh-pages deployments

.github/workflows/publish-docs.yml

@@ -41,6 +41,6 @@ jobs:
       - name: Deploy to `${{ inputs.destination_dir }}` directory of `gh-pages` branch
         uses: peaceiris/actions-gh-pages@068dc23d9710f1ba62e86896f84735d869951305
         with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
+          github_token: ${{ secrets.DEPLOY_TOKEN }}
           publish_dir: ./docs
           destination_dir: ${{ inputs.destination_dir }}