how to add around each author using wp_list_authors

If you require customized solution then you can use user query like this.

<?php

    $args  = array(
        'who' => 'authors',
        'orderby' => 'display_name'
    );

    $wp_user_query = new WP_User_Query($args);

    if ( ! empty( $wp_user_query->results ) ) {
        foreach ( $wp_user_query->results as $user ) {

            echo '<span class="abc"><a href="' . get_author_posts_url( $user->ID ) . '">' . $user->display_name . '</a></span>';

        }
    }

?>