Creating 1.4.0-beta.1 version release (Azure#49132)

* Update token exchange API routes to be called, prevent update of scopes through options

Update route and api version in  token exchange API called by credential routes to be consistent by REST API review.
Make sure that update of scopes in EntraCommunicationTokenCredential won't affect already constructed EntraTokenCredential.

* Fixed typos

* Release 1.4.0-beta.1 release day

Author: paveldostalms

sdk/communication/Azure.Communication.Common/CHANGELOG.md

@@ -1,18 +1,12 @@
 # Release History
 
-## 1.4.0-beta.1 (Unreleased)
+## 1.4.0-beta.1 (2025-04-01)
 
 ### Features Added
 - Introduced support for `Azure.Core.TokenCredential` with `EntraCommunicationTokenCredentialOptions`, enabling Entra users to authorize Communication Services and allowing an Entra user with a Teams license to use Teams Phone Extensibility features through the Azure Communication Services resource.
 - Added support for a new communication identifier `TeamsExtensionUserIdentifier` which maps rawIds with format `8:acs:{resourceId}_{tenantId}_{userId}`.
 - Added `IsAnonymous` and `AssertedId` properties to `PhoneNumberIdentifier`.
 
-### Breaking Changes
-
-### Bugs Fixed
-
-### Other Changes
-
 ## 1.3.0 (2024-02-13)
 
 ### Features Added