public async Task GetUsersById_WhenUSerNotFound_ReturnsUSerNotFoundResponse()
{
var userId = Guid.NewGuid();
_mockUserManger.Setup(e => e.FindByIdAsync(userId.ToString()))
.ReturnsAsync((User)null);
var mappedUser = Fixture.Create <UserDto>();
mockUserMapper.Setup(e => e.MapToModel(It.IsAny <User>()))
.Returns(mappedUser);
var response = await sut.GetUsersById(userId);
response.IsSuccess.Should().BeFalse();
response.ResponseException !.ErrorCode.Should().Be(ErrorCode.UserNotFound);
response.ResponseException.ErrorMessage.Should().Be(ErrorCode.UserNotFound.GetDescription());
}