Don't handle lack of IPv6 as fatal in unit tests

src/test.cpp

@@ -1517,6 +1517,8 @@ struct TestSocket: public TestBase
 			const char sendbuffer[] = "hello world!";
 			IPv6AddressBytes bytes;
 			bytes.bytes[15] = 1;
+			
+			try {
 				socket6.Send(Address(&bytes, port), sendbuffer, sizeof(sendbuffer));
 
 				sleep_ms(50);
@@ -1534,6 +1536,11 @@ struct TestSocket: public TestBase
 				UASSERT(strncmp(sendbuffer, rcvbuffer, sizeof(sendbuffer))==0);
 				UASSERT(memcmp(sender.getAddress6().sin6_addr.s6_addr, Address(&bytes, 0).getAddress6().sin6_addr.s6_addr, 16) == 0);
 			}
+			catch (SendFailedException e) {
+				errorstream << "IPv6 support enabled but not available!" << std::endl;
+ 			}
+			
+		}
 
 		// IPv4 socket test
 		{