why does Microsoft.Data.SqlClient v3 reference Azure.Identity?

Edited by @mdaigle:
The scope of this work is splitting entra authentication methods (e.g. Authentication=ActiveDirectoryDefault or Authentication=Active Directory Managed Identity in the connection string) into a separate Microsoft.Data.SqlClient.Extensions.Azure package. As a consequence, Azure.Identity, Azure.Core, and Microsoft.Identity.Client dependencies are removed from the core Microsoft.Data.SqlClient package.

This work is available as of version 7.0.0. Customers who rely on entra authentication methods should take a dependency on Microsoft.Data.SqlClient.Extensions.Azure. See release notes for additional details.

Removal of Microsoft.IdentityModel.XXX dependencies is tracked separately under #4017.