[site-reviews-forms] restrict products in dropdown to a category

add_filter('site-reviews-forms/builder/assigned_posts/args', function ($args) {
    if ('product' === $args['post_type'] ?? 0) {
        $args['tax_query'] = [[
            'field' => 'slug',
            'taxonomy' => 'product_cat',
            'terms' => ['red-products'], // change as needed
        ]];
    }
    return $args;
});