chore: update doc (#23354)

README.md

@@ -85,11 +85,6 @@ You can also try out Element Plus with its built-in component playground.
 <table align="center" cellspacing="0" cellpadding="0">
   <tbody>
     <tr>
-      <td align="center" valign="middle">
-        <a href="https://doc.buildadmin.com/?from=element-plus" target="_blank">
-          <img width="130px" src="https://user-images.githubusercontent.com/17680888/173179536-30e35fd1-cd5a-482a-bc41-9d5f0aa66fd4.png">
-        </a>
-      </td>
       <td align="center" valign="middle">
         <a href="https://el.frsimple.com" target="_blank">
           <img width="130px" src="https://github.com/user-attachments/assets/27ec522b-5de2-4c61-88b9-be47ff3ccc69">

docs/.vitepress/config/sponsors.ts

@@ -17,14 +17,6 @@ export const rightRichTextSponsors: Sponsor[] = []
 export const rightBigLogoSponsors: Sponsor[] = []
 
 export const rightLogoSmallSponsors: Sponsor[] = [
-  {
-    name: 'BuildAdmin',
-    img: '/images/buildadmin.png',
-    imgL: '/images/buildadmin-l.png',
-    url: 'https://doc.buildadmin.com/?from=element-plus',
-    slogan: 'Vue3 open source admin system',
-    slogan_cn: 'Vue3企业级开源后台管理系统',
-  },
   {
     name: 'frsimple',
     img: '/images/frsimple.png',