added scopes to notification API

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/NotificationManagementService.java

@@ -142,9 +142,7 @@ public interface NotificationManagementService {
                             message = "Error occurred while updating notification status.")
             }
     )
-    @Permission(
-            scope = "",
-            permissions = { "" }
+    @Permission(scope = "notification:modify", roles = {"admin"}
     )
     Response updateNotificationStatus(
             @ApiParam(