public async Task Handle(UpdateRetroState command)
        {
            var retrospective = await _store.GetById <Retrospective>(command.RetrospectiveId);

            retrospective.UpdateRetroState(command.ParticipantId, command.State);
            await _store.Save(retrospective, retrospective.Version);
        }
        public async Task <IActionResult> UpdateRetroState(string participantId, Guid retrospectiveId, RetrospectiveState state)
        {
            var cmd = new UpdateRetroState(retrospectiveId, participantId, state);
            await _cmdSender.Send(cmd);

            var response = RedirectToAction("Get", new { retrospectiveId = retrospectiveId });

            return(response);
        }