fix(ProdPlan): Get SubAssy Items does not work (#27537)

* fix(ProdPlan): Get SubAssy Items does not work

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* fix: make form dirty when subassy item are fetched
diff --git a/erpnext/manufacturing/doctype/production_plan/production_plan.js b/erpnext/manufacturing/doctype/production_plan/production_plan.js
index db0f2c5..2bd02da 100644
--- a/erpnext/manufacturing/doctype/production_plan/production_plan.js
+++ b/erpnext/manufacturing/doctype/production_plan/production_plan.js
@@ -242,6 +242,8 @@
 	},
 
 	get_sub_assembly_items: function(frm) {
+		frm.dirty();
+
 		frappe.call({
 			method: "get_sub_assembly_items",
 			freeze: true,
diff --git a/erpnext/manufacturing/doctype/production_plan/production_plan.py b/erpnext/manufacturing/doctype/production_plan/production_plan.py
index a28fc7a..18284e0 100644
--- a/erpnext/manufacturing/doctype/production_plan/production_plan.py
+++ b/erpnext/manufacturing/doctype/production_plan/production_plan.py
@@ -561,8 +561,6 @@
 			get_sub_assembly_items(row.bom_no, bom_data, row.planned_qty)
 			self.set_sub_assembly_items_based_on_level(row, bom_data, manufacturing_type)
 
-		self.save()
-
 	def set_sub_assembly_items_based_on_level(self, row, bom_data, manufacturing_type=None):
 		bom_data = sorted(bom_data, key = lambda i: i.bom_level)