Predefined Radio Options not working

[Daveiano]

Follow up from #13

Predefined options are also not working for Radios. This is because there is an explicit check in WebformElementOptions:

if (is_string($value['#options']) && $value['plugin'] instanceof Select) {
    $value['#options'] = WebformOptions::getElementOptions($value);
}

should be

if (is_string($value['#options']) && ($value['plugin'] instanceof Select || $value['plugin'] instanceof Radios)) {
    $value['#options'] = WebformOptions::getElementOptions($value);
}