feat: support lossless online/offline

spring-cloud-tencent-plugin-starters/spring-cloud-starter-tencent-discovery-adapter-plugin/pom.xml

@@ -24,7 +24,7 @@
 			<groupId>com.alibaba.cloud</groupId>
 			<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
 			<version>2021.1</version>
-			<scope>test</scope>
+			<optional>true</optional>
 		</dependency>
 
 		<dependency>

spring-cloud-tencent-plugin-starters/spring-cloud-starter-tencent-discovery-adapter-plugin/src/main/java/com/tencent/cloud/plugin/discovery/adapter/transformer/NacosRegistrationTransformer.java

@@ -30,8 +30,8 @@ public class NacosRegistrationTransformer implements RegistrationTransformer {
 
 	@Override
 	public void transformCustom(DefaultInstance instance, Registration registration) {
-		if (registration instanceof NacosRegistration nacosRegistration) {
-			NacosDiscoveryProperties nacosDiscoveryProperties = nacosRegistration.getNacosDiscoveryProperties();
+		if (registration instanceof NacosRegistration) {
+			NacosDiscoveryProperties nacosDiscoveryProperties = ((NacosRegistration) registration).getNacosDiscoveryProperties();
 			String namespace = nacosDiscoveryProperties.getNamespace();
 			if (StringUtils.isBlank(namespace)) {
 				namespace = "default";