Update installer immediately if network connection is already established

[tmerten]

Description

I was already connected to WiFi when launching the subiquity installer. It then took me through the steps of selecting a keyboard layout, selecting a network (IMO it's unlikely that I want to use a different network at this point) and then it asked to update. After the update, it started from the beginning again choosing a keyboard layout (second time) and a network (third time).

IMO it'd be more convenient if it could either

• ask to update immediately before doing anything else, if connected to network or
• store the configuration done so far (e.g. in a temp file) and resume at the step that comes after the update.

Additional context

No response