add TODO maker as review reqirement

Author: dzhangalibaba

files/build_templates/docker_image_ctl.j2

@@ -113,6 +113,7 @@ function preStartAction()
     fi
 
     echo -n "" > /tmp/snmpagentaddr.yml
+    # TODO
     # we should avoid using 'keys' operation via redis-cli or sonic-db-cli
     # there would be an issue when KEY in database contains space or '\n'
     # for loop on the non-tty 'keys' output will take the space or `\n` as seperator when parsing the element