Support 'Approved Client Apps' condition for CA on MacOS devices.

Since MacOS Mail app has started ot support modern Auth in MacOS 10.14 (Mojave) it is no longer possible to block that app from accessing exchange online without also blocking Outlook on the platform too.

The ask is to be able to block the Mac Mail client app on Mojave but NOT Outlook and the obvious resolution is to extend support for the 'Approved Client App' condition that currently only supports iOS and Android, though another resolution would be equally welcome if the outcome is the same.