Remove nested middleware array

Thanks, @harikt!

Author: weierophinney

doc/book/cookbook/setting-locale-depending-routing-parameter.md

@@ -143,7 +143,7 @@ return [
             'middleware' => [
                 Zend\Expressive\Container\ApplicationFactory::ROUTING_MIDDLEWARE,
                 Helper\UrlHelperMiddleware::class,
-                [ 'middleware' => LocalizationMiddleware::class ],
+                LocalizationMiddleware::class,
                 Zend\Expressive\Container\ApplicationFactory::DISPATCH_MIDDLEWARE,
             ],
             'priority' => 1,