Update open collective links

index.html

@@ -289,14 +289,15 @@
         </div>
         <div class="suppoer-banners" style="text-align: center">
           <div class="sponsors">
-            <a href="https://opencollective.com/grapesjs" target="_blank">
-              <img src="https://opencollective.com/grapesjs/sponsors.png" alt="Become a Sponsor">
-            </a>
+            <a href="https://opencollective.com/grapesjs/sponsors/0/website" target="_blank"><img src="https://opencollective.com/grapesjs/sponsors/0/avatar"></a>
+            <a href="https://opencollective.com/grapesjs/sponsors/2/website" target="_blank"><img src="https://opencollective.com/grapesjs/sponsors/2/avatar"></a>
+            <a href="https://opencollective.com/grapesjs/sponsors/3/website" target="_blank"><img src="https://opencollective.com/grapesjs/sponsors/3/avatar"></a>
           </div>
           <div class="backers">
-            <a href="https://opencollective.com/grapesjs" target="_blank">
-              <img src="https://opencollective.com/grapesjs/backers.png" alt="Become a Backers">
-            </a>
+            <a href="https://opencollective.com/grapesjs/backers/0/website" target="_blank"><img src="https://opencollective.com/grapesjs/backers/0/avatar"></a>
+            <a href="https://opencollective.com/grapesjs/backers/1/website" target="_blank"><img src="https://opencollective.com/grapesjs/backers/1/avatar"></a>
+            <a href="https://opencollective.com/grapesjs/backers/2/website" target="_blank"><img src="https://opencollective.com/grapesjs/backers/2/avatar"></a>
+            <a href="https://opencollective.com/grapesjs/backers/3/website" target="_blank"><img src="https://opencollective.com/grapesjs/backers/3/avatar"></a>
           </div>
         </div>
       </div>