- [x] I have searched the [issues](https://github.com/apache/dubbo/issues) of this repository and believe that this is not a duplicate.
- [x] I have checked the [FAQ](https://github.com/apache/dubbo/blob/master/FAQ.md) of this repository and believe that this is not a duplicate.

### Environment

* Dubbo version: master
* Operating System version: all platform
* Java version: all version

### Steps to reproduce this issue

1. set SystemProperty "java.net.preferIPv6Addresses" to true.
2. call org.apache.dubbo.common.utils.NetUtils#isPreferIPV6Address().
3. check the return value.

### Expected Result

org.apache.dubbo.common.utils.NetUtils#isPreferIPV6Address() will return true when SystemProperty "java.net.preferIPv6Addresses" set to true.

### Actual Result

org.apache.dubbo.common.utils.NetUtils#isPreferIPV6Address() method ignore SystemProperty "java.net.preferIPv6Addresses" and always return false
NetworkInterface i = (NetworkInterface) interfaces.nextElement();
            Enumeration addresses = i.getInetAddresses();
            while (addresses.hasMoreElements()) {
                InetAddress address = (InetAddress) addresses.nextElement();
                if (preferIpv6 && address instanceof Inet6Address) {
                    try {
                        if(address.isReachable(100)){
                            multicastSocket.setInterface(address);
                            interfaceSet = true;
                            break;
                        }
                    } catch (IOException e) {
                        
                    }
                } else if (!preferIpv6 && address instanceof Inet4Address) {
                    try {
                        if(address.isReachable(100)){
                            multicastSocket.setInterface(address);
                            interfaceSet = true;
                            break;
                        }
                    } catch (IOException e) {
                        
                    }
                }
            }
            if (interfaceSet) {
                break;
            }
        }