add: mysqltest description 2

tools/deploy/obd.sh

@@ -576,6 +576,7 @@ function main() {
   then 
     NEED_REBOOT="1"
   fi
+  export OBD_FORCE_UPDATE_PLUGINS=1
   if [[ ! -f $OBD_HOME/.obd/.obd_environ || "$(grep '"OBD_DEV_MODE": "1"' $OBD_HOME/.obd/.obd_environ)" == "" ]]
   then
   obd devmode enable || (echo "Exec obd cmd failed. If your branch is based on 3.1_opensource_release, please go to the deps/3rd directory and execute 'bash dep_create.sh all' to install obd." && exit 1)