Revert "fix(stock): set item_name to fetch if empty in packing slip item (backport #58925)"

erpnext/stock/doctype/packing_slip_item/packing_slip_item.json

@@ -41,7 +41,6 @@
   },
   {
    "fetch_from": "item_code.item_name",
-   "fetch_if_empty": 1,
    "fieldname": "item_name",
    "fieldtype": "Data",
    "in_list_view": 1,
@@ -150,4 +149,4 @@
  "sort_order": "DESC",
  "states": [],
  "track_changes": 1
-}
+}