public async Task <ActionResult <string> > PostLogin(LoginDto dto)
        {
            var user = await _identityContract.GetUserByName(dto.UserName);

            if (user == null)
            {
                ModelState.AddModelError($"用户{dto.UserName}", "不存在");
                return(BadRequest(ModelState));
            }
            if (!user.Password.Equals(dto.Password))
            {
                ModelState.AddModelError("密码", "错误");
                return(BadRequest(ModelState));
            }
            string token = CreateJwtToken(user);

            return(Ok(token));
        }