Deprecate Authentication=ActiveDirectoryPassword

[David-Engel]

Given the direction of Azure authentication and enforcement of mandatory MFA, we should deprecate the ActiveDirectoryPassword Authentication option on SqlConnections. MSAL and Azure.Identity are also planning to deprecate their corresponding APIs soon.

For more details of the Azure plan, see Planning for mandatory multifactor authentication for Azure and other admin portals

I don't think we have any APIs we need to annotate (unfortunately - would be nice to be able to provide compile time warnings). Otherwise, this just means updating the public docs, and including it in the next release announcement.

We should consider logging an INFO or WARN message if the option is used as we don't have other good signals to users to stop using the option.

Let me know if I'm missing anything else.