public void TestAuthenticate()
        {
            var bearerToken = "bearerToken";

            BearerTokenAuthenticator authenticator = new BearerTokenAuthenticator(bearerToken);
            IClient client = new IBMHttpClient();

            authenticator.Authenticate(client);

            Assert.IsNotNull(client);
            Assert.IsNotNull(client.BaseClient);
            Assert.IsNotNull(client.BaseClient.DefaultRequestHeaders.Authorization);
            Assert.IsTrue(client.BaseClient.DefaultRequestHeaders.Authorization.ToString() == "Bearer " + bearerToken);
        }