public async Task TestAddUserAsync_VerifyInsertAsyncCalledOnce()
{
var mockRepository = new Mock <IUserRepository>();
var manageUser = new ManageUser(mockRepository.Object, fixture.ManageUserLogger);
var user = new User();
var result = await manageUser.AddUserAsync(user);
mockRepository.Verify(r => r.InsertAsync(user), Times.Once);
}