COW-9638 Update nack method to return bool instead of void to match 5.10 and 7.0+

- Change return type from void to bool in Connection::nack()
- Return the result of the underlying AMQPQueue::nack() call
- This allows callers to determine if the nack operation was successful

Author: Oleg Namaka

src/Symfony/Component/Messenger/Bridge/Amqp/Transport/Connection.php

@@ -491,9 +491,9 @@ public function ack(\AMQPEnvelope $message, string $queueName, int $flags = \AMQ
         $this->queue($queueName)->ack($message->getDeliveryTag(), $flags);
     }
 
-    public function nack(\AMQPEnvelope $message, string $queueName, int $flags = \AMQP_NOPARAM): void
+    public function nack(\AMQPEnvelope $message, string $queueName, int $flags = \AMQP_NOPARAM): bool
     {
-        $this->queue($queueName)->nack($message->getDeliveryTag(), $flags);
+        return $this->queue($queueName)->nack($message->getDeliveryTag(), $flags) ?? true;
     }
 
     public function setup(): void