Update CHANGELOG.md

Author: ramsessanchez

CHANGELOG.md

@@ -11,6 +11,25 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+## [5.42.0] - 2022-12-07
+
+### Added
+
+- AnonymousGuestConversationMember model and related requests. 
+- MicrosoftAccountUserConversationMember model and related requests. 
+- SkypeForBusinessUserConversationMember model and related requests. 
+- SkypeUserConversationMember model and related requests. 
+- Security Namespace Additions: 
+- EdiscoveryPurgeDataOperation model and related requests.
+- EdiscoverySearchPurgeData model and related requests. 
+- PurgeAreas model. 
+- PurgeType model.  
+ 
+### Changed
+
+- Generated v1.0 models and request builders using Typewriter.
+- Classes related to the removed and added models/requests have been updated to reflect the addition and removal of these models/requests.
+
 ## [5.41.0] - 2022-11-09
 
 ### Added