fix channel_group dependency in demo_vpc_domain.pp
fix channel_group dependency in demo_vpc_domain.pp

cisco/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module,cisco/cisco-network-puppet-module,cisco/cisco-network-puppet-module,cisco/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module