update SG tile

Author: kenieva

articles/governance/index.yml

@@ -42,14 +42,14 @@ productDirectory:
         - url: ./management-groups/index.yml
           text: See more >
     - title: Azure Service Groups
-      imageSrc: ./media/management-groups.svg
+      imageSrc: ./media/service-groups.png
       links:
         - url: ./service-groups/overview.md
-          text: Developer overview
+          text: Overview
         - url: ./service-groups/create-service-group-rest-api.md
           text: Create a service group using the REST API
         - url: ./service-groups/create-service-group-member-rest-api.md
-          text: Connect resources or resource containers to service groups 
+          text: Add service groups members
         - url: ./service-groups/manage-service-groups.md
           text: Manage Service Groups
     - title: Azure Policy