update changelog (#20631)

sdk/identity/identity/CHANGELOG.md

@@ -1,19 +1,14 @@
 # Release History
 
-## 2.1.0-beta.1 (Unreleased)
+## 2.1.0-beta.1 (2022-03-02)
 
 ### Features Added
 
 - Added support for specifying a custom `resourceId` when creating a `ManagedIdentityCredential` or `DefaultAzureCredential`.
   - In some scenarios where a user-assigned managed identity is required, the identity may be known by an ARM resource ID, but not a client ID (such as when user-assigned identities are created using an ARM template). The `resourceId` option allows an app to select its managed identity by its ARM resource ID to support such scenarios.
   - If `resourceId` is provided, the managed identity providers for Azure App Service (2017), Azure Arc, Azure Cloud Shell, Azure Service Fabric and Token Exchange authentication will log a warning since this parameter is not supported by the identity endpoints in those services. The authentication attempts will be sent, but the parameter will be ignored by the service.
 - Added `clientId` to the optional parameters of the `ManagedIdentityCredential`.
-
-### Breaking Changes
-
-### Bugs Fixed
-
-### Other Changes
+- Updated the Troubleshoot guide to have error codes and error messages for the Identity Customer Service Support.
 
 ## 2.0.4 (2022-02-18)