public void watch(final String key, final Consumer<Object> consumer) {
        watchUpstreamListener.put(key, consumer);
    }
Refresh.

@param key      contextPath
@param consumer consumer
shenyu-plugin/shenyu-plugin-proxy/shenyu-plugin-rpc/shenyu-plugin-grpc/src/main/java/org/apache/shenyu/plugin/grpc/cache/ApplicationConfigCache.java