Improve wording of join channel UI form restrictions
Improve wording of join channel UI form restrictions

This gives a more actionable message to the user if they do not enter a valid value.

MaxLeiter/lounge,FryDay/lounge,ScoutLink/lounge,williamboman/lounge,MaxLeiter/lounge,ScoutLink/lounge,realies/lounge,williamboman/lounge,MaxLeiter/lounge,williamboman/lounge,thelounge/lounge,FryDay/lounge,thelounge/lounge,realies/lounge,realies/lounge,ScoutLink/lounge,FryDay/lounge