func (engine *DockerTaskEngine) openEventstream(ctx context.Context) error {
	events, err := engine.client.ContainerEvents(ctx)
	if err != nil {
		return err
	}
	engine.events = events
	return nil
}
func (engine *DockerTaskEngine) openEventstream(ctx context.Context) error {
	events, err := engine.client.ContainerEvents(ctx)
	if err != nil {
		return err
	}
	engine.events = events
	return nil
}
// openEventstream opens, but does not consume, the docker event stream