docs/about: add more links (#4974)

site/content/en/about/_index.html

@@ -14,7 +14,7 @@ menu:
   <h3 class="mb-4">About Us</h3>
   <p>CVAT was designed to provide users with a set of convenient instruments for annotating digital images and videos. <br/>
     CVAT supports supervised machine learning tasks pertaining to object detection, image classification, image segmentation
-    and 3D data annotation. It allows users to annotate images with multiple tools 
+    and 3D data annotation. It allows users to annotate images with multiple tools
     (boxes, polygons, cuboids, circles, skeletons, etc).</p>
 </div>
 
@@ -90,6 +90,9 @@ menu:
 
     <div class="row">
         <ul class="col-lg-6 text-left">
+          <li>
+            Visit <a href="https://www.cvat.ai/">CVAT.AI</a>
+          </li>
           <li>
             You can ask questions anytime in <a href="https://gitter.im/opencv-cvat/public">public Gitter chat</a>.
           </li>
@@ -104,6 +107,9 @@ menu:
           <li>
             Visit our <a href="https://github.com/opencv/cvat">GitHub</a> repository.
           </li>
+          <li>
+            Check out our <a href="https://discord.gg/fNR3eXfk6C">Discord channel</a>
+          </li>
         </ul>
     </div>
 </div>