How to Hide the "WHMCS Recent Sales pop-up" Admin Menu

function plt_hide_recent_sales_popup_for_web_hosting_companies_and_whmcs_users_menus() {
	//Hide the "WHMCS Recent Sales pop-up" menu.
	remove_menu_page('hpsalespopup');
}

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

Where do I put this code?