minor #10540 Update dispatch example (martinssipenko)

This PR was merged into the 4.1 branch.

Discussion
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Update dispatch example

Dispatch method returns `void`. The change fixes confusion that bus can return things.

Commits
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7607866 Update dispatch example

Author: javiereguiluz

components/messenger.rst

@@ -70,7 +70,7 @@ Example::
         ])),
     ]);
 
-    $result = $bus->dispatch(new MyMessage(/* ... */));
+    $bus->dispatch(new MyMessage(/* ... */));
 
 .. note::