chore: update sponsors [ci skip] (#11420)

Author: vue-bot

Diff for: BACKERS.md

@@ -189,11 +189,6 @@ Funds donated via Patreon go directly to support Evan You's full-time work on Vu
           <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/pullrequest.svg?sanitize=true">
         </a>
       </td>
-      <td align="center" valign="middle">
-        <a href="https://unicorn.io/" target="_blank">
-          <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/unicorn_io.png">
-        </a>
-      </td>
       <td align="center" valign="middle">
         <a href="https://www.vuescreencasts.com/" target="_blank">
           <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/happy_programmer_llc.png">

Diff for: README.md

@@ -194,11 +194,6 @@ Funds donated via Patreon go directly to support Evan You's full-time work on Vu
           <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/pullrequest.svg?sanitize=true">
         </a>
       </td>
-      <td align="center" valign="middle">
-        <a href="https://unicorn.io/" target="_blank">
-          <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/unicorn_io.png">
-        </a>
-      </td>
       <td align="center" valign="middle">
         <a href="https://www.vuescreencasts.com/" target="_blank">
           <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/happy_programmer_llc.png">