public void Test0110_RefreshAuthzHttpChallenge()
        {
            using (var signer = new RS256Signer())
            {
                signer.Init();
                using (var fs = new FileStream($"{BASE_LOCAL_STORE}TestRegister.acmeSigner", FileMode.Open))
                {
                    signer.Load(fs);
                }

                AcmeRegistration reg;
                using (var fs = new FileStream($"{BASE_LOCAL_STORE}TestRegister.acmeReg", FileMode.Open))
                {
                    reg = AcmeRegistration.Load(fs);
                }

                using (var client = new AcmeClient())
                {
                    client.RootUrl = _rootUrl;
                    client.Signer = signer;
                    client.Registration = reg;
                    client.Init();

                    client.GetDirectory(true);

                    AuthorizationState authzState;
                    using (var fs = new FileStream($"{BASE_LOCAL_STORE}TestAuthz.acmeAuthz", FileMode.Open))
                    {
                        authzState = AuthorizationState.Load(fs);
                    }

                    client.RefreshAuthorizeChallenge(authzState, "simpleHttp", true);

                    using (var fs = new FileStream($"{BASE_LOCAL_STORE}TestAuthz-HttpChallengeRefreshed.acmeAuthz", FileMode.Create))
                    {
                        authzState.Save(fs);
                    }
                }
            }
        }