minor symfony#13708 Added return value to make the example work as is (apiv-thomas)

This PR was submitted for the 5.0 branch but it was merged into the 4.4 branch instead.

Discussion
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Added return value to make the example work as is

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f362b28 Added return value to make the example work as is

Author: javiereguiluz

console/commands_as_services.rst

@@ -45,6 +45,8 @@ For example, suppose you want to log something from within your command::
         {
             $this->logger->info('Waking up the sun');
             // ...
+            
+            return 0;
         }
     }