fix: allow Leave Encashment amount to be editable frappe#1275

Refer : frappe#1275

hrms/hr/doctype/leave_encashment/leave_encashment.py

@@ -158,6 +158,8 @@ def set_leave_balance(self):
 		self.leave_allocation = allocation.name
 
 	def set_encashment_amount(self):
+		if not self.is_new():
+            		return	
 		if not hasattr(self, "_salary_structure"):
 			self.set_salary_structure()