Компонент для email'ов перемещён в common

api/models/authentication/RegistrationForm.php

@@ -2,7 +2,7 @@
 namespace api\models\authentication;
 
 use api\components\ReCaptcha\Validator as ReCaptchaValidator;
-use api\emails\EmailHelper;
+use common\emails\EmailHelper;
 use api\models\base\ApiForm;
 use common\helpers\Error as E;
 use common\components\UserFriendlyRandomKey;