release notes

Author: mgravell

docs/ReleaseNotes.md

@@ -11,6 +11,7 @@ Current package versions:
 - Add support for new `BITOP` operations in CE 8.2 ([#2900 by atakavci](https://github.com/StackExchange/StackExchange.Redis/pull/2900))
 - Package updates ([#2906 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2906))
 - Fix handshake error with `CLIENT ID` ([#2909 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2909))
+- Support async cancellation of `SCAN` enumeration ([#2911 by mgravell](https://github.com/StackExchange/StackExchange.Redis/pull/2911)) 
 
 ## 2.8.41