How to Hide the "Required Taxonomies" Admin Menu

function plt_hide_required_taxonomies_menus() {
	//Hide the "Settings → Required Taxonomies" menu.
	remove_submenu_page('options-general.php', 'wprtt_welcome_page');
}

add_action('admin_menu', 'plt_hide_required_taxonomies_menus', 11);

Where do I put this code?