[gitpod-setup] fix the preview opening issue.

.gitpod.yml

@@ -1,9 +1,10 @@
 tasks:
+  - command: gp await-port 3000 && sleep 3 && gp preview $(gp url 3000)
   - init: npm install
     command: npm run dev
 ports:
   - port: 3000
-    onOpen: open-preview
+    onOpen: ignore
 vscode:
   extensions:
     - sysoev.language-stylus@1.11.0:xX39oruAJ5UQzTNVRdbBaQ==

README.md

@@ -68,7 +68,9 @@ Move to [awesome-docsify](https://github.com/docsifyjs/awesome-docsify#showcase)
 | [docute](https://github.com/egoist/docute)       | 📜 Effortlessly documentation done right |
 | [docpress](https://github.com/docpress/docpress) | Documentation website generator          |
 
-## Online one-click setup for Contributing
+## Contributing
+
+### Online one-click setup for Contributing
 
 You can use Gitpod(A free online VS Code-like IDE) for contributing. With single click it'll launch a workspace and automatically: