bug #3792 Update commands_as_services.rst (mimol91)

This PR was submitted for the master branch but it was merged into the 2.4 branch instead (closes #3792).

Discussion
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Update commands_as_services.rst

Missing parent construct

Commits
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a28de44 Update commands_as_services.rst

cookbook/console/commands_as_services.rst

@@ -90,6 +90,8 @@ have some ``NameRepository`` service that you'll use to get your default value::
 
         public function __construct(NameRepository $nameRepository)
         {
+            parent::__construct();
+            
             $this->nameRepository = $nameRepository;
         }