How to Hide the "Zendesk Chat Settings" Admin Menu

function plt_hide_widget_for_zendesk_chat_via_api_menus() {
	//Hide the "Settings → Zendesk Chat Settings" menu.
	remove_submenu_page('options-general.php', 'widget-for-zendesk-chat-via-api');
}

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

Where do I put this code?