[docs] add CNAME when deploying website

.github/workflows/deploy_docs.yml

@@ -62,6 +62,7 @@ jobs:
                   github_token: ${{ secrets.GITHUB_TOKEN }}
                   # Build output to publish to the `gh-pages` branch:
                   publish_dir: ./docs/build
+                  cname: compositor.live
                   # The following lines assign commit authorship to the official
                   # GH-Actions bot for deploys to `gh-pages` branch:
                   user_name: github-actions[bot]