update_packages requires undefined BatchPromoteData

[dbabineau-vr]

when using update_packages on the npm_client with "promote" as the operation, the NpmPackagesBatchRequest requires a BatchPromoteData object that isn't defined anywhere:

    # TODO: Requires a BatchPromoteData model that doesn't even exist!
    batch_request = NpmPackagesBatchRequest(data=promote_data, operation="promote", packages=packages)
    response = npm_client.update_packages(batch_request, feed.id, project=args.project)