Update toc.yml

Author: Juliako

articles/media-services/video-indexer/toc.yml

@@ -15,6 +15,10 @@
   items:
   - name: Use Video Indexer API
     href: video-indexer-use-apis.md
+- name: Samples
+  items:
+  - name: Video Indexer samples
+    href: https://github.com/Azure-Samples/media-services-video-indexer
 - name: Concepts
   items:
   - name: Overview