Bugfix: BulkQuery->QueryTicker spammed errors if items list was empty

TradeSkillMaster/TradeSkillMaster.lua

@@ -716,6 +716,7 @@ end
 
 -- Bulk load uncached IDs.  Divides in to buckets of 50
 function TSMAPI:BulkQuery(items)
+	if not items or #items == 0 then return end
 	self.QueryTicker = Timer.NewTicker(1, function()
 		Item:BulkContinueOnLoad(table.take(items, 50), function(id) end, function(id) return GetItemInfo(id) == nil end) -- 3rd parameter (validator) is optional
 		if #items == 0 then