For some reason, when you cancelled summoning an ERT it would say that
you could not find any candidates (there wasn't a poll to begin with,
the summon was cancelled), so I moved messaging to
`proc/make_emergency_response_team()` so that we can better communicate
that.
🆑 tonty
admin: Cancelling an ERT summon will now say so instead of saying there
were no candidates
/🆑
1e3f8bb525