in build/BuildSteps.cs [275:279]
public static void AddBundleZipFile(string rootPath, BundlePackageConfiguration packageConfig)
{
string bundleZipDestinationPath = Path.Combine(rootPath, packageConfig.GeneratedBundleZipFileName);
FileUtility.CopyFile(packageConfig.GeneratedBundleZipFilePath, bundleZipDestinationPath);
}