Updating Azure.Identity changelog for 1.5.0-beta.4 release (#23880)
Updating Azure.Identity changelog for 1.5.0-beta.4 release (#23880)

* Updating Azure.Identity changelog for 1.5.0-beta.4 release

* remove unused header

* Update sdk/identity/Azure.Identity/CHANGELOG.md

Co-authored-by: Christopher Scott <2ae7117bb7669fe7b354c821186d6adf012c6106@hotmail.com>

Co-authored-by: Christopher Scott <2ae7117bb7669fe7b354c821186d6adf012c6106@hotmail.com>
AsrOneSdk/azure-sdk-for-net,AsrOneSdk/azure-sdk-for-net,AsrOneSdk/azure-sdk-for-net,AsrOneSdk/azure-sdk-for-net