Add Azure AD User as auth_plugin option

[AdamCoulterOz]

Affected Resource

mysql_user

Add support for Azure AD User creation as an auth_plugin option:

SET aad_auth_validate_oids_in_tenant = OFF;
CREATE AADUSER 'myuser' IDENTIFIED BY 'CLIENT_ID';

[AdamCoulterOz]

I've had a look at it, could do a PR for it.

[AdamCoulterOz]

This would also require being able to login to mysql using an oauth token which requires an additional parameter --enable-cleartext-plugin