Migrate from ADAL to MSAL or Azure.Identity

[abatishchev]

Currently Microsoft.IdentityModel.Clients.ActiveDirectory (aka ADAL) is used to authenticate with AAD:

ARMClient/Directory.Packages.props

Line 8 in aae17e0

<PackageVersion Include="Microsoft.IdentityModel.Clients.ActiveDirectory" Version="2.28.0" />

But even its latest version 5.3.0 is decommissioned as of December 2022:

Suggested Alternatives
[Microsoft.Identity.Client](https://www.nuget.org/packages/Microsoft.Identity.Client/)

Additional Details
Please note, a newer package is available Microsoft.Identity.Client.
This package will continue to receive critical bug fixes until December 2022, we strongly encourage you to upgrade.
See https://docs.microsoft.com/azure/active-directory/develop/msal-net-migration for Migration guide and more details.

We should migrate to either MSAL (per the guidance) or Azure.Identity (my personal preference).