How can I allow an app to make changes without typing in the password, but using TouchID on the Touch Bar instead?
MacBook Pro, 13", 2016, macOS Sierra 10.12.6
This is not one of the supported features of Touch ID on macOS - at least not yet.
With Touch ID on your MBP, you can:
Undoubtedly as time goes by, more functionality will be added to Touch ID on macOS - but the ability to use it to allow apps to make changes to macOS isn't available yet.