Use the background portal to request running at startup

[danirabbit]

https://github.com/JeysonFlores/switcher/blob/d4f488ff3280853a54c7dd606f253734719063e9/com.github.jeysonflores.switcher.yml#L15

Instead of adding a sandbox hole here, there is a portal for asking users to allow your app to run at startup. Apologies that it's not well-documented yet, but I've filed an issue report against docs with more info and reference material: https://github.com/elementary/docs/issues/159