force 2fa for group of users (#456)

Authored-by: Antonio Cordeddu <coranto@yetopen.com>

tests/_fixtures/AssignmentFixture.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace tests\_fixtures;
+
+use yii\test\ActiveFixture;
+
+class AssignmentFixture extends ActiveFixture
+{
+    public $modelClass = 'Da\User\Model\Assignment';
+    public $tableName = 'auth_assignment';
+}