Add video link for Immersive Reader

Author: metanMSFT

articles/cognitive-services/immersive-reader/index.yml

@@ -24,6 +24,10 @@ landingContent:
         links:
           - text: What is Immersive Reader?
             url: overview.md
+      - linkListType: video
+        links:
+          - text: Getting started - short engineering videos
+            url: https://techcommunity.microsoft.com/t5/education-blog/getting-started-documentation-and-videos-for-partners-using/ba-p/700709
 
   - title: Get started
     linkLists: