add MockNamingService methods

spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-nacos-discovery/src/test/java/com/alibaba/cloud/nacos/registry/MockNamingService.java

@@ -68,6 +68,16 @@ public class MockNamingService implements NamingService {
 
 	}
 
+	@Override
+	public void batchRegisterInstance(String serviceName, String groupName, List<Instance> instances) throws NacosException {
+
+	}
+
+	@Override
+	public void batchDeregisterInstance(String serviceName, String groupName, List<Instance> instances) throws NacosException {
+
+	}
+
 	@Override
 	public void deregisterInstance(String serviceName, String ip, int port)
 			throws NacosException {