[bansync] Servers that listen to each other cascade bans during softban action

[EternalllZM]

The softban mod action in core's mod causes a cascading ban action effect if two servers listen to each other for bans.

user is softbanned on server 1
ban syncs to server 2
user is unbanned on server 1
user is banned on server 1 again due to ban syncing to server 2 prior to unban syncing

This results in the user being banned from both servers, unbanned from neither.

[PhasecoreX]

Interesting, I didn't know what a softban was until now. So I'll need to add some sort of queue or something to make sure each ban or unban event propagates fully before handling the next event.