public void TestMessageParsingTwoValues()
        {
            string cypherText = "AZ";

            var cryptoMessage = new EncryptedMessage(cypherText);

            cryptoMessage.GetValues().Should().Equal(1, 26);
        }
        public void TestMessageParsingSingleValue1()
        {
            string cypherText = "A";

            var cryptoMessage = new EncryptedMessage(cypherText);

            cryptoMessage.GetValues().Should().Equal(1);
        }