fix: Enhancement in credit note (#18511)

* fix: Credit note enhancement

* Fix: Print format for Sales Invoice Return

* fix: Zero quantity validation fix for credit note

erpnext/controllers/accounts_controller.py

@@ -60,7 +60,9 @@ class AccountsController(TransactionBase):
 
 	def validate(self):
 
-		self.validate_qty_is_not_zero()
+		if not self.get('is_return'):
+			self.validate_qty_is_not_zero()
+
 		if self.get("_action") and self._action != "update_after_submit":
 			self.set_missing_values(for_validate=True)