code: public function onDelete(ResourceEventInterface $event)
      {
          $shipment = $this->getShipmentFromEvent($event);
  
          //$this->invoiceSynchronizer->synchronize($shipment);
  
          $sale = $this->getSaleFromShipment($shipment);
  
          $sale->removeShipment($shipment);
  
          $this->scheduleSaleContentChangeEvent($sale);
      }
docs: Delete event handler.
  
  @param ResourceEventInterface $event