Clarification based on feedback

https://msazure.visualstudio.com/One/_workitems/edit/12476641

Author: spelluru

articles/service-bus-messaging/message-expiration.md

@@ -2,7 +2,7 @@
 title: Azure Service Bus - message expiration
 description: This article explains about expiration and time to live of Azure Service Bus messages. After such a deadline, the message is no longer delivered.
 ms.topic: conceptual
-ms.date: 07/09/2021
+ms.date: 11/01/2021
 ---
 
 # Message expiration (Time to Live)
@@ -57,6 +57,7 @@ Here's what considered idleness of entities (queues, topics, and subscriptions):
     - No sends  
     - No updates to the topic  
     - No scheduled messages 
+    - No operations on the topic's subscriptions (as shown below)
 - Subscriptions
     - No receives  
     - No updates to the subscription