mesos: set zookeeper_server_group for agents
mesos: set zookeeper_server_group for agents

this variable is required when installing mesos agents

datascienceinc/mantl,CiscoCloud/mantl,mantl/mantl,sehqlr/mantl,bitium/mantl,KaGeN101/mantl,phnmnl/mantl,mantl/mantl,sehqlr/mantl,KaGeN101/mantl,bitium/mantl,phnmnl/mantl,CiscoCloud/microservices-infrastructure,CiscoCloud/mantl,datascienceinc/mantl,CiscoCloud/microservices-infrastructure