## 问题描述
使用如下方式配置RegistryConfig bean时

```java
    @Bean
    public RegistryConfig registryConfig() {
        RegistryConfig registryConfig = new RegistryConfig();
        registryConfig.setProtocol("zookeeper");
        registryConfig.setAddress("localhost");
        registryConfig.setPort(2181);
        return registryConfig;
    }
```

提示无法与zookeeper建立连接，调试代码发现，zookeeper链接为

`zookeeper://localhost:9090/ConfigCenterConfig?check=true&config-file=dubbo.properties&group=dubbo&highest-priority=false&namespace=dubbo&timeout=3000`

使用了9090端口，未使用2181端口，registryConfig.setPort()不生效。

对比测试，使用registryConfig.setAddress("localhost:2181")方式可以生效。


}
        });
        asyncReferringFutures.clear();
        cache.destroyAll();
    }
    private void registerServiceInstance() {
        if (CollectionUtils.isEmpty(getServiceDiscoveries())) {
            return;
        }
        ApplicationConfig application = getApplication();
        String serviceName = application.getName();
        URL exportedURL = selectMetadataServiceExportedURL();
        String host = exportedURL.getHost();
        int port = exportedURL.getPort();
        ServiceInstance serviceInstance = createServiceInstance(serviceName, host, port);
        getServiceDiscoveries().forEach(serviceDiscovery -> serviceDiscovery.register(serviceInstance));
    }
    private URL selectMetadataServiceExportedURL() {
        URL selectedURL = null;
        SortedSet<String> urlValues = metadataService.getExportedURLs();
        for (String urlValue : urlValues) {
            URL url = URL.valueOf(urlValue);
            if (MetadataService.class.getName().equals(url.getServiceInterface())) {
                continue;
            }
            if ("rest".equals(url.getProtocol())) { 
                selectedURL = url;
                break;
            } else {
                selectedURL = url;