- [ ] I have searched the [issues](https://github.com/apache/dubbo/issues) of this repository and believe that this is not a duplicate.
- [ ] 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: 2.7.5
* Zookeeper version: 3.4.14
* Operating System version: macos
* Java version: 1.8

### Steps to reproduce this issue

1. 按官方文档搭建provider，两种方式：annotation/xml
2. 分别配置

```xml
    <dubbo:metadata-report address="zookeeper://127.0.0.1:2181"/>
```

```java
        @Bean
        public MetadataReportConfig metadataReportConfig() {
            MetadataReportConfig metadataReportConfig = new MetadataReportConfig();
            metadataReportConfig.setAddress("zookeeper://127.0.0.1:2181");
            return metadataReportConfig;
        }
```

3. 应用正常启动
4. Consumer端正常调用
4. 观察Zookeeper节点数据，元数据节点/dubbo/metadata 未创建

### Expected Result
元数据正常上报

### Actual Result

元数据节点在Zookeeper上未创建，元数据未上报

> 将dubbo版本号更改为2.7.4.1、2.7.3，代码或配置未改动，元数据正常上报

* The {@link Protocol} implementation with adaptive functionality,it will be different in different scenarios.
     * A particular {@link Protocol} implementation is determined by the protocol attribute in the {@link URL}.
     * For example:
     *
     * <li>when the url is registry://224.5.6.7:1234/org.apache.dubbo.registry.RegistryService?application=dubbo-sample,
     * then the protocol is <b>RegistryProtocol</b></li>
     *
     * <li>when the url is dubbo://224.5.6.7:1234/org.apache.dubbo.config.api.DemoService?application=dubbo-sample, then
     * the protocol is <b>DubboProtocol</b></li>
     * <p>
     * Actually，when the {@link ExtensionLoader} init the {@link Protocol} instants,it will automatically wraps two
     * layers, and eventually will get a <b>ProtocolFilterWrapper</b> or <b>ProtocolListenerWrapper</b>
     */
    private static final Protocol REF_PROTOCOL = ExtensionLoader.getExtensionLoader(Protocol.class).getAdaptiveExtension();
    /**
     * The {@link Cluster}'s implementation with adaptive functionality, and actually it will get a {@link Cluster}'s
     * specific implementation who is wrapped with <b>MockClusterInvoker</b>
     */
    private static final Cluster CLUSTER = ExtensionLoader.getExtensionLoader(Cluster.class).getAdaptiveExtension();
    /**
     * A {@link ProxyFactory} implementation that will generate a reference service's proxy,the JavassistProxyFactory is
     * its default implementation
     */
    private static final ProxyFactory PROXY_FACTORY = ExtensionLoader.getExtensionLoader(ProxyFactory.class).getAdaptiveExtension();
    /**
     * The interface proxy reference
     */
    private transient volatile T ref;
    /**
     * The invoker of the reference service