minor #15797 [Messenger] Add missing space in custom-transport.rst (JeroenMoonen)

This PR was submitted for the 5.3 branch but it was merged into the 4.4 branch instead.

Discussion
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[Messenger] Add missing space in custom-transport.rst

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Commits
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a3b5a13 Add missing space in custom-transport.rst doc

Author: javiereguiluz

messenger/custom-transport.rst

@@ -65,7 +65,7 @@ Here is a simplified example of a database transport::
                     WHERE (delivered_at IS NULL OR delivered_at < :redeliver_timeout)
                     AND handled = FALSE'
                 )
-                ->setParameter('redeliver_timeout', new DateTimeImmutable('-5minutes'))
+                ->setParameter('redeliver_timeout', new DateTimeImmutable('-5 minutes'))
                 ->getOneOrNullResult();
 
             if (null === $row) {