code: public function getConfigTreeBuilder()
      {
          $treeBuilder = new TreeBuilder();
          $rootNode = $treeBuilder->root('mm_media');
  
          $this->addMediaTypesSection($rootNode);
          // Here you should define the parameters that are allowed to
          // configure your bundle. See the documentation linked above for
          // more information on that topic.
  
          return $treeBuilder;
      }
docs: {@inheritdoc}