was selling items at a vendor, put an item into the "Sell Junk" button. and error occurred:

Date: 2020-05-04 18:34:49
ID: 2
Error occured in: Global
Count: 1
Message: ..\AddOns\Scrap\addons\merchant\learning.lua line 56:
attempt to index global 'L' (a nil value)
Debug:
[string "=[C]"]: ?
[string "@scrap\addons\merchant\learning.lua"]:56: OnItemSold()
[string "@scrap\addons\merchant\learning.lua"]:26:
Scrap\addons\merchant\learning.lua:24
[string "=[C]"]: UseContainerItem()
[string "@..\FrameXML\ContainerFrame.lua"]:1332: ContainerFrameItemButton_OnClick()
[string ":OnClick"]:12:
[string ":OnClick"]:1
[string "=[C]"]: ?
Locals:

This is a copy of #87