public static void ClientUpdatedWithoutLastName()
        {
            Client c = new Client("Nom", "Prénom", 0123456789, "*****@*****.**");

            try
            {
                c.UpdateLastName("");
            }
            catch (Exception)
            {
            }
            Assert.False(c.LastName.Equals(""));
        }
        public static void ClientUpdatedWithValidLastName()
        {
            Client c = new Client("Nom", "Prénom", 0123456789, "*****@*****.**");
            string n = "NouveauNom";

            try
            {
                c.UpdateLastName(n);
            }
            catch (Exception)
            {
            }
            Assert.True(c.LastName.Equals(n));
        }