Merge pull request #35701 from ruthra-kumar/typeerror_on_exchange_rate_revaluation

fix: typeerror on exchange rate revaluation
diff --git a/erpnext/stock/stock_ledger.py b/erpnext/stock/stock_ledger.py
index a668ab8..b3ed220 100644
--- a/erpnext/stock/stock_ledger.py
+++ b/erpnext/stock/stock_ledger.py
@@ -962,6 +962,7 @@
 				item.current_amount = flt(item.current_qty) * flt(item.current_valuation_rate)
 
 				item.amount = flt(item.qty) * flt(item.valuation_rate)
+				item.quantity_difference = item.qty - item.current_qty
 				item.amount_difference = item.amount - item.current_amount
 			else:
 				sr.difference_amount = sum([item.amount_difference for item in sr.items])