public override async Task<IEnumerable<ConnectedServiceInstance>> EnumerateServiceInstancesAsync(CancellationToken ct)
{
IEnumerable<IAzureIoTHub> hubs = await this.Authenticator.GetAzureIoTHubs(this.iotHubAccountManager, ct).ConfigureAwait(false);
ct.ThrowIfCancellationRequested();
return hubs.Select(p => AzureIoTHubAccountProviderGrid.CreateServiceInstance(p)).ToList();
}