public function addVersion(PackageEvent $event)
    {
        $package = $this->getPackageFromOperation($event->getOperation());

        if ($package->getName() === self::ACF_PRO_PACKAGE_NAME) {
            $version = $this->validateVersion($package->getPrettyVersion());
            $package->setDistUrl(
                $this->addParameterToUrl($package->getDistUrl(), 't', $version)
            );
        }
    }