feature #12045 [Messenger] InMemoryTransport ignore acknowledged and rejected messages (tienvx)

This PR was submitted for the master branch but it was merged into the 4.4 branch instead (closes #12045).

Discussion
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[Messenger] InMemoryTransport ignore acknowledged and rejected messages

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Commits
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354b84d [Messenger] InMemoryTransport ignore acknowledged and rejected messages

Author: OskarStark

messenger.rst

@@ -964,7 +964,7 @@ during a request::
 
             /* @var InMemoryTransport $transport */
             $transport = self::$container->get('messenger.transport.async_priority_normal');
-            $this->assertCount(1, $transport->get());
+            $this->assertCount(1, $transport->getSent());
         }
     }