docs: update site config (#5416)

- add v3 link to nav menu
- remove vercel config

Author: thonatos

.github/workflows/gh-pages.yml

@@ -25,7 +25,7 @@ jobs:
       run: npm i -g npminstall && npminstall
 
     - name: Build Documents
-      run: npm run site:build && cp vercel.json ./site/dist/vercel.json
+      run: npm run site:build
 
     - name: Deploy Documents
       uses: peaceiris/actions-gh-pages@v3

.github/workflows/vercel-preview.yml

@@ -39,20 +39,28 @@ export default defineConfig({
         title: 'Plugins',
         path: 'https://github.com/search?q=topic%3Aegg-plugin&type=Repositories',
       },
+      {
+        title: 'v3.x',
+        path: 'https://v3.eggjs.org',
+      },
     ],
     'zh-CN': [
       null,
       {
         title: 'GitHub',
         path: 'https://github.com/eggjs/egg',
       },
+      {
+        title: '发布日志',
+        path: 'https://github.com/eggjs/egg/releases',
+      },
       {
         title: '插件列表',
         path: 'https://github.com/search?q=topic%3Aegg-plugin&type=Repositories',
       },
       {
-        title: '发布日志',
-        path: 'https://github.com/eggjs/egg/releases',
+        title: 'v3.x',
+        path: 'https://v3.eggjs.org',
       },
     ],
   },