edit wait script

wait_for_container.sh

 #!/bin/sh
 
-sleep 300
 
-until $(docker ps -qf "name=vhr18-pvs_renderer"); do
+while [ -z $(docker ps -qf "name=vhr18-pvs_renderer")]; do
     >&2 echo "Container is unavailable - sleeping"
     sleep 15
   done
\ No newline at end of file