addPaymentChangeable example

$response = new OrderRouteResponse($orderResult);
        if ($request->get('checkPromotion') === true) {
            foreach ($orders as $order) {
                $promotions = $this->getActivePromotions($order, $context);
                $changeable = true;
                foreach ($promotions as $promotion) {
                    $changeable = $this->checkPromotion($promotion);
                    if ($changeable === true) {
                        break;
                    }
                }
                $response->addPaymentChangeable([$order->getId() => $changeable]);
            }
        }

        return $response;
    }

    private function getActivePromotions(OrderEntity $order, SalesChannelContext $context): PromotionCollection
    {
        $promotionIds = [];
        foreach ($order->getLineItems() ?? [] as $lineItem) {
            $payload = $lineItem->getPayload();