[monotouch-test] Disable test that uses TcpClient on watchOS, since TcpClient doesn't work on watchOS.

tests/monotouch-test/Security/SecureTransportTest.cs

@@ -148,6 +148,8 @@ namespace MonoTouchFixtures.Security {
 			Assert.That (ssl_client_ciphers, Is.EqualTo (ssl_server_ciphers), "same");
 		}
 
+#if !__WATCHOS__
+		// This test uses sockets (TcpClient), which doesn't work on watchOS.
 		[Test]
 		public void Tls12 ()
 		{
@@ -192,5 +194,6 @@ namespace MonoTouchFixtures.Security {
 				Assert.That (s, Is.StringStarting ("HTTP/1.0 302 Found").Or.StringStarting ("HTTP/1.0 200 OK"), "response");
 			}
 		}
+#endif // !__WATCHOS__
 	}
 }