[site-reviews] auto-create user categories

/**
 * Automatically create a category for each user that submits a review
 * This category can then be used to target the user reviews
 * i.e. [site_reviews category=u_13] - u_13 is the category slug for the author with an user ID of 13
 * @param \GeminiLabs\SiteReviews\Review $review
 * @return void
 */
add_action('site-reviews/review/created', function ($review) {
    if ($user = get_userdata($review->user_id)) {
        $term = 'u_'.$user->ID;
        $taxonomy = glsr()->taxonomy;
        if (!term_exists($term, $taxonomy)) {
            wp_insert_term($user->display_name, $taxonomy, ['slug' => $term]);
        }
        wp_set_object_terms($review->ID, $term, $taxonomy);
    }
});