eliminated the double quotes

src/Symfony/Bundle/DebugBundle/DependencyInjection/Configuration.php

@@ -59,7 +59,7 @@ public function getConfigTreeBuilder()
                 ->children()
                     ->enumNode('theme')
                         ->info('Changes the color of the dump() output when rendered directly on the templating. "dark" (default) or "light"')
-                        ->example('"dark"')
+                        ->example('dark')
                         ->values(array('dark', 'light'))
                         ->defaultValue('dark')
                     ->end()