minor #16167 Update handler_results.rst (erop)

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

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Update handler_results.rst

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Commits
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89a5ee0 Update handler_results.rst

Author: javiereguiluz

messenger/handler_results.rst

@@ -11,7 +11,7 @@ You can use this to get the value returned by the handler(s)::
     use Symfony\Component\Messenger\MessageBusInterface;
     use Symfony\Component\Messenger\Stamp\HandledStamp;
 
-    $envelope = $messageBus->dispatch(SomeMessage());
+    $envelope = $messageBus->dispatch(new SomeMessage());
 
     // get the value that was returned by the last message handler
     $handledStamp = $envelope->last(HandledStamp::class);