Retroactively update AMQP's changelog (#5321)

Co-authored-by: Anton Kolesnyk <[email protected]>

Author: antkmsft

sdk/core/azure-core-amqp/CHANGELOG.md

@@ -14,7 +14,7 @@
 
 ### Features Added
 
-The `Close` method on AMQP Message Sender and Message Receiver now blocks until the client receives a `DETACH` response from the remote node.
+- The `Close` method on AMQP Message Sender and Message Receiver now blocks until the client receives a `DETACH` response from the remote node.
 
 ### Breaking Changes