code: protected function registerMarkdown()
      {
          $app = $this->app;
  
          $app->singleton('markdown', function ($app) {
              return new Converter($app['commonmark.docparser'], $app['commonmark.htmlrenderer']);
          });
  
          $app->alias('markdown', Converter::class);
      }
docs: Register the CommonMarkConverter.
  
  @return void