How to Hide the "Cloudbridge Mattermost" Admin Menu

function plt_hide_cloudbridge_mattermost_menus() {
	//Hide the "Settings → Cloudbridge Mattermost" menu.
	remove_submenu_page('options-general.php', 'cloudbridge-mattermost');
}

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

Where do I put this code?