chore: update sponsors [ci skip] (#10750)

BACKERS.md

@@ -225,8 +225,13 @@ Funds donated via Patreon go directly to support Evan You's full-time work on Vu
         </a>
       </td>
       <td align="center" valign="middle">
-        <a href="https://staffaugmentation.ro/en" target="_blank">
-          <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/staff_augmentation.png">
+        <a href="http://www.pullrequest.com" target="_blank">
+          <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/pullrequest.svg">
+        </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.svg">
         </a>
       </td>
       <td align="center" valign="middle">
@@ -234,6 +239,8 @@ 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/piratebay_proxy.png">
         </a>
       </td>
+    </tr><tr></tr>
+    <tr>
       <td align="center" valign="middle">
         <a href="https://www.programmers.io" target="_blank">
           <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/programmers_io.png">

README.md

@@ -230,8 +230,13 @@ Funds donated via Patreon go directly to support Evan You's full-time work on Vu
         </a>
       </td>
       <td align="center" valign="middle">
-        <a href="https://staffaugmentation.ro/en" target="_blank">
-          <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/staff_augmentation.png">
+        <a href="http://www.pullrequest.com" target="_blank">
+          <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/pullrequest.svg">
+        </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.svg">
         </a>
       </td>
       <td align="center" valign="middle">
@@ -239,6 +244,8 @@ 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/piratebay_proxy.png">
         </a>
       </td>
+    </tr><tr></tr>
+    <tr>
       <td align="center" valign="middle">
         <a href="https://www.programmers.io" target="_blank">
           <img width="148px" src="https://raw.githubusercontent.com/vuejs/vuejs.org/master/themes/vue/source/images/programmers_io.png">