add_filter( 'submit_job_steps', 'replace_done_with_redirect' );

function replace_done_with_redirect( $steps ) {
    $steps['done'] = array(
        'priority' => 30,
        'handler' => function() {
            if ( wp_redirect( job_manager_get_permalink( 'job_dashboard' ) ) ) {
                exit;
            }
        }
    );
    return $steps;
}