Merge branch '5.1' into 5.2

* 5.1:
  Fix merge

Author: nicolas-grekas

Tests/Transport/AmqpReceiverTest.php

@@ -18,7 +18,6 @@
 use Symfony\Component\Messenger\Bridge\Amqp\Transport\Connection;
 use Symfony\Component\Messenger\Envelope;
 use Symfony\Component\Messenger\Exception\TransportException;
-use Symfony\Component\Messenger\Tests\Fixtures\DummyMessage;
 use Symfony\Component\Messenger\Transport\AmqpExt\AmqpReceivedStamp;
 use Symfony\Component\Messenger\Transport\AmqpExt\AmqpReceiver;
 use Symfony\Component\Messenger\Transport\AmqpExt\Connection;