Add extra coffers when generating dungeon.

As a reward for pressing on.

abms.lua

@@ -344,6 +344,7 @@ minetest.register_abm({
 	nodenames = {"fun_caves:coffer"},
 	interval = 2,
 	chance = 50,
+	catch_up = false,
 	action = function(p0, node, _, _)
 		minetest.remove_node(p0)
 	end,