public async Task <IActionResult> AssignApplicationUser(int applicationId, int userId)
        {
            var result = await _applicationService.AssignApplicationUserAsync(applicationId, userId);

            if (!result.Success)
            {
                return(BadRequest(result.Message));
            }

            var scheduleResource = _mapper.Map <User, UserResource>(result.Resource.User);

            return(Ok(scheduleResource));
        }