api: fix wrong response object type of listTrafficTypes API

Author: weizhouapache

api/src/main/java/org/apache/cloudstack/api/command/admin/usage/ListTrafficTypesCmd.java

@@ -26,14 +26,13 @@
 import org.apache.cloudstack.api.Parameter;
 import org.apache.cloudstack.api.response.ListResponse;
 import org.apache.cloudstack.api.response.PhysicalNetworkResponse;
-import org.apache.cloudstack.api.response.ProviderResponse;
 import org.apache.cloudstack.api.response.TrafficTypeResponse;
 
 import com.cloud.network.PhysicalNetworkTrafficType;
 import com.cloud.user.Account;
 import com.cloud.utils.Pair;
 
-@APICommand(name = "listTrafficTypes", description = "Lists traffic types of a given physical network.", responseObject = ProviderResponse.class, since = "3.0.0",
+@APICommand(name = "listTrafficTypes", description = "Lists traffic types of a given physical network.", responseObject = TrafficTypeResponse.class, since = "3.0.0",
         requestHasSensitiveInfo = false, responseHasSensitiveInfo = false)
 public class ListTrafficTypesCmd extends BaseListCmd {