Dubbo Version: 3.0.10
注册失败，unexport时，subscribeUrl和registerUrl此时为空，需要判断空处理。 
<img width="944" alt="image" src="https://user-images.githubusercontent.com/12670328/200469537-41a4ccb5-adda-4231-9f71-9af9fec2172d.png">


private final URL subscribeUrl;
        private final Invoker originInvoker;
        private List<Configurator> configurators;
        public OverrideListener(URL subscribeUrl, Invoker originalInvoker) {
            this.subscribeUrl = subscribeUrl;
            this.originInvoker = originalInvoker;
        }
        /**
         * @param urls The list of registered information, is always not empty, The meaning is the same as the
         *             return value of {@link org.apache.dubbo.registry.RegistryService#lookup(URL)}.
         */
        @Override
        public synchronized void notify(List<URL> urls) {
            if (logger.isDebugEnabled()) {
                logger.debug("original override urls: " + urls);
            }
            List<URL> matchedUrls = getMatchedUrls(urls, subscribeUrl);
            if (logger.isDebugEnabled()) {
                logger.debug("subscribe url: " + subscribeUrl + ", override urls: " + matchedUrls);
            }
            
            if (matchedUrls.isEmpty()) {
                return;