public void EmailContactWithInValidEmailAddressIsNotValid()
        {
            // Arrange
            EmailContact emailContact = new EmailContact("testexample.com");

            // Act
            bool isValid = emailContact.IsValid;

            // Assert
            Assert.IsFalse(isValid);
        }
        public void EmptyEmailContactIsNotValid()
        {
            // Arrange
            EmailContact emailContact = new EmailContact("");

            // Act
            bool isValid = emailContact.IsValid;

            // Assert
            Assert.IsFalse(isValid);
        }