[balenaOS] Implement Update Settings

[benfrancis]

As a user I want to enable or disable automatic updates on balenaOS, so that I have more control over which version of the application I'm running.

[benfrancis]

Not sure how feasible this is on balenaOS.

[benfrancis]

Note to self: Updates can't really be disabled on balenaOS, so just need to make sure it shows the current version and remove the option to toggle automatic updates on and off.