//Use just
add_shortcode( ‘wp_nav_menu_additional-resources_items’, ‘wp_nav_menu_additional-resources_items’ );
//And inside some text
[wp_nav_menu_additional-resources_items]
//Use just
add_shortcode( ‘wp_nav_menu_additional-resources_items’, ‘wp_nav_menu_additional-resources_items’ );
//And inside some text
[wp_nav_menu_additional-resources_items]