Cast to string when passing to MailFormatHelper::htmlToText() (#5218)

* Cast to string when passing to MailFormatHelper::htmlToText()

* PHP CS

Co-authored-by: Moshe Weitzman <weitzman@tejasa.com>

src/Drupal/DrupalUtil.php

@@ -20,7 +20,7 @@ public static function drushRender($data): string
             $data = \Drupal::service('renderer')->renderRoot($data);
         }
 
-        $data = MailFormatHelper::htmlToText($data);
+        $data = MailFormatHelper::htmlToText((string) $data);
         return $data;
     }
 }