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

### Environment

* Dubbo version: 2.7.14、3.0.4

### Steps to reproduce this issue

1. start dubbo admin (nacos registry)

The ```EventListener``` instance has created countless times by the scheduled task(```scheduledExecutorService```) and cached in the ```InstancesChangeNotifier#listenerMap```(Nacos)  , until the memory is full.

- NacosRegistry
```
private void subscribeEventListener(String serviceName, final URL url, final NotifyListener listener)
        throws NacosException {
        EventListener eventListener = new RegistryChildListenerImpl(serviceName, url, listener);
        namingService.subscribe(serviceName,
            getUrl().getGroup(Constants.DEFAULT_GROUP),
            eventListener);
}
```

- InstancesChangeNotifier
```
private final Map<String, ConcurrentHashSet<EventListener>> listenerMap = new ConcurrentHashMap<String, ConcurrentHashSet<EventListener>>();

public void registerListener(String serviceName, String clusters, EventListener listener) {
        String key = ServiceInfo.getKey(serviceName, clusters);
        ConcurrentHashSet<EventListener> eventListeners = listenerMap.get(key);
        if (eventListeners == null) {
            synchronized (lock) {
                eventListeners = listenerMap.get(key);
                if (eventListeners == null) {
                    eventListeners = new ConcurrentHashSet<EventListener>();
                    listenerMap.put(key, eventListeners);
                }
            }
        }
        eventListeners.add(listener);
}
```
The ```namingService.subscribe```  is finally called to the ```InstancesChangeNotifier#registerListener``` , so 
eventListener cached in  eventListeners.

![image](https://user-images.githubusercontent.com/5037807/140080041-f617bda2-0f48-4669-8e3d-2184a6eb9a75.png)



String[] segments = serviceName.split(SERVICE_NAME_SEPARATOR, -1);
            int length = segments.length;
            if (length != 4) { 
                return false;
            }
            String category = segments[CATEGORY_INDEX];
            if (!categories.contains(category)) { 
                return false;
            }
            String serviceInterface = segments[SERVICE_INTERFACE_INDEX];
            
            if (!WILDCARD.equals(targetServiceInterface) &&
                !StringUtils.isEquals(targetServiceInterface, serviceInterface)) {
                return false;
            }
            
            String version = segments[SERVICE_VERSION_INDEX];
            if (!WILDCARD.equals(targetVersion) && !StringUtils.isEquals(targetVersion, version)) {
                return false;
            }
            String group = segments[SERVICE_GROUP_INDEX];
            return group == null || WILDCARD.equals(targetGroup) || StringUtils.isEquals(targetGroup, group);
        });
    }
    private <T> void filterData(Collection<T> collection, NacosDataFilter<T> filter) {
        
        collection.removeIf(data -> !filter.accept(data));