Add support for azuresql dialect

[sblackstone]

The MSSQL driver has different driver names based on whether your connecting with a ManagedIdentity or by password.

This corresponds to https://github.com/microsoft/go-mssqldb/tree/main/azuread

This small patch adds support for azuresql driver and treats it as a synonym to sqlserver

[mfridman]

Hehe, thanks. This is the kind of thing I'm hoping to avoid (in /v4), i.e., the goose package should be initialized with a dialect but the *sql.DB connection should be supplied by the caller.

That way anyone can use whatever driver they want, and match it up to a dialect that makes sense for their database technology.

This also makes it more extensible into the future when new drivers are added by the community.