Update gh-pages.yml

Re-enables the `cname` setting in the GitHub Actions script.

Author: Logofile

.github/workflows/gh-pages.yml

@@ -33,4 +33,4 @@ jobs:
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./public
-          # cname: protobuf.dev
+          cname: protobuf.dev