minor #19871 [Messenger] Add missing asterisk (asispts)

This PR was merged into the 5.4 branch.

Discussion
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[Messenger] Add missing asterisk

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Commits
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6afab45 Add missing asterisk

messenger.rst

@@ -1745,7 +1745,7 @@ during a request::
 
             $this->assertSame(200, $client->getResponse()->getStatusCode());
 
-            /* @var InMemoryTransport $transport */
+            /** @var InMemoryTransport $transport */
             $transport = $this->getContainer()->get('messenger.transport.async_priority_normal');
             $this->assertCount(1, $transport->getSent());
         }