fix: zero rm-cost for batch rm item in SCR (#34616)

fix: `0` rm-cost for batch rm item in SCR
diff --git a/erpnext/controllers/subcontracting_controller.py b/erpnext/controllers/subcontracting_controller.py
index cc80f6c..0575429 100644
--- a/erpnext/controllers/subcontracting_controller.py
+++ b/erpnext/controllers/subcontracting_controller.py
@@ -455,7 +455,7 @@
 					"allow_zero_valuation": 1,
 				}
 			)
-			rm_obj.rate = get_incoming_rate(args)
+			rm_obj.rate = bom_item.rate if self.backflush_based_on == "BOM" else get_incoming_rate(args)
 
 		if self.doctype == self.subcontract_data.order_doctype:
 			rm_obj.required_qty = qty