Fix docker-compose depends_on contains an invalid type issue
Fix docker-compose depends_on contains an invalid type issue

$ wget https://isardvdi.com/docker-compose.yml
$ docker-compose -v
docker-compose version 1.25.0, build unknown
$ docker-compose up
ERROR: The Compose file './docker-compose.yml' is invalid because:
services.isard-engine.depends_on contains an invalid type, it should be an array

isard-vdi/isard,isard-vdi/isard,isard-vdi/isard,isard-vdi/isard,isard-vdi/isard