WORLDGUARD-3508 - Reported by PseudoKnight

Reported by SullyTheUnusual in the forums.

It appears the event listener is getting the item in hand instead of the resulting item when checking for a milk bucket. This causes the break block event to be checked when it shouldn't. I think it should be getItemStack().getType() instead of getBucket() in this event.
https://github.com/sk89q/WorldGuard/blob/master/src/main/java/com/sk89q/worldguard/bukkit/listener/EventAbstractionListener.java#L454