Update changelog (#441)

Changelog.md

@@ -16,6 +16,7 @@ This release **fully supports .NET 6+** for both server and client without havin
   * This change came in WCF Ria Services SP1  [WCF Ria Services SP1](https://jeffhandley.com/2011-03-10/riaservicesv1sp1rtm)
     > DataForm Add/Remove for EntitySet and EntityCollection
 With our initial V1.0 release, many of you found that a DataForm bound to an EntitySet or an EntityCollection did not support the Add or Remove buttons.  This was a difficult cut to make in V1.0, so I’m pleased to announce that with V1.0 SP1, this is now supported.  Silverlight 4 introduced the [ICollectionViewFactory](http://msdn.microsoft.com/en-us/library/system.componentmodel.icollectionviewfactory(VS.95).aspx) interface, with support integrated into DataGrid and DataForm, and both EntitySet and EntityCollection now implement that interface to allow the Add/Remove features to light up.
+* The WCF based `WebDomainClientFactory` will not receive any new changes and is now marked as obsolete. It is recommeded to switch to `OpenRiaServices.Client.DomainClients.BinaryHttpDomainClientFactory` instead.
 
 ### Other
 * Run E2E tests against AspNetCore hosting