- [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
String host;
        int port;
        if (i > -1) {
            host = address.substring(0, i);
            port = Integer.parseInt(address.substring(i + 1));
        } else {
            host = address;
            port = 0;
        }
        return new InetSocketAddress(host, port);
    }
    public static String toURL(String protocol, String host, int port, String path) {
        StringBuilder sb = new StringBuilder();
        sb.append(protocol).append("://");
        sb.append(host).append(':').append(port);
        if (path.charAt(0) != '/') {
            sb.append('/');
        }
        sb.append(path);
        return sb.toString();
    }
    public static void joinMulticastGroup(MulticastSocket multicastSocket, InetAddress multicastAddress) throws IOException {
        setInterface(multicastSocket, multicastAddress instanceof Inet6Address);
        multicastSocket.setLoopbackMode(false);
        multicastSocket.joinGroup(multicastAddress);
    }
    public static void setInterface(MulticastSocket multicastSocket, boolean preferIpv6) throws IOException {
        boolean interfaceSet = false;
        Enumeration interfaces = NetworkInterface.getNetworkInterfaces();
        while (interfaces.hasMoreElements()) {