manifests/site: add a new hypervisor, hypervisor3
manifests/site: add a new hypervisor, hypervisor3

SoftwareHeritage/puppet-swh-site,SoftwareHeritage/puppet-swh-site,SoftwareHeritage/puppet-swh-site,SoftwareHeritage/puppet-swh-site,SoftwareHeritage/puppet-swh-site