How to Hide the "Lazy Load" Admin Menu

function plt_hide_sarvarov_lazy_load_menus() {
	//Hide the "Settings → Lazy Load" menu.
	remove_submenu_page('options-general.php', 'sarvarov_lazy_load_settings');
}

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

Where do I put this code?