Easy way to test MRs directly on the devkit

There are some components that can only really properly tested on the devkit. Building things in Builder works for basic UI stuff, but for cellular, or touch, and some other things you really need to test it on the devkit. I've run into this issue quite a few times for Contacts, Calls, Chatty, Phosh, Squeekboard, and others.

Building MRs on the devkit is too time consuming to realistically do for every MR, so it would be good to have an easier way to just get a deb/flatpak to test onto the devkit.