silverstripe-userforms: Checkbox validation error is appearing

Note that… getSourceAsArray() function is missed in version 4.2.2. Can you please merge the following code? or not sure is this feature?

    /**
     * @inheritdoc
     *
     * @return array
     */
    public function getSourceAsArray()
    {
        $array = parent::getSourceAsArray();
        return array_values($array);
    }