Carry appName in FetchClusterServerInfo command

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

sentinel-cluster/sentinel-cluster-server-default/src/main/java/com/alibaba/csp/sentinel/cluster/server/command/handler/FetchClusterServerInfoCommandHandler.java

@@ -27,6 +27,7 @@ import com.alibaba.csp.sentinel.command.CommandHandler;
 import com.alibaba.csp.sentinel.command.CommandRequest;
 import com.alibaba.csp.sentinel.command.CommandResponse;
 import com.alibaba.csp.sentinel.command.annotation.CommandMapping;
+import com.alibaba.csp.sentinel.util.AppNameUtil;
 import com.alibaba.fastjson.JSONArray;
 import com.alibaba.fastjson.JSONObject;
 
@@ -69,6 +70,9 @@ public class FetchClusterServerInfoCommandHandler implements CommandHandler<Stri
             .fluentPut("namespaceSet", namespaceSet)
             .fluentPut("embedded", ClusterServerConfigManager.isEmbedded());
 
+        // Since 1.5.0 the appName is carried so that the caller can identify the appName of the token server.
+        info.put("appName", AppNameUtil.getAppName());
+
         return CommandResponse.ofSuccess(info.toJSONString());
     }