public async Task CanChangeKey()
        {
            using (var client = new AcmeClient(WellKnownServers.LetsEncryptStaging))
            {
                var reg = await client.NewRegistraton();

                var newKey = new AccountKey().Export();
                await client.ChangeKey(reg, newKey);

                await client.DeleteRegistration(reg);
            }
        }
        public async Task RunAccountFlow(KeyAlgorithm algorithm)
        {
            var dirUri = await IntegrationHelper.GetAcmeUriV1();

            var key = new AccountKey(algorithm);

            using (var client = new AcmeClient(IntegrationHelper.GetAcmeHttpHandler(dirUri)))
            {
                client.Use(key.Export());
                var reg = await client.NewRegistraton();

                reg.Data.Agreement = reg.GetTermsOfServiceUri();

                await client.UpdateRegistration(reg);

                var newKey = new AccountKey().Export();
                await client.ChangeKey(reg, newKey);

                await client.DeleteRegistration(reg);
            }
        }