Sort checklist items by deadline, soonest first

[RobRuana]

The sorted_checklist here is never actually sorted. We need to do something like this:

return {
    'message': message,
    'guest': guest,
    'sorted_checklist': sorted(sorted_checklist, key=lambda x: guest.deadline_from_model(x['name']))
}

Checklist items out of order:

[kitsuta]

Oh, whoops.. I had that working at one point! Good catch! 😅