[lyon][hydra] Add Hydra cluster (Grace Hopper machines)

data/grid5000/sites/lyon/clusters/hydra/hydra.json

data/grid5000/sites/lyon/clusters/hydra/nodes/hydra-1.json

data/grid5000/sites/lyon/clusters/hydra/nodes/hydra-2.json

data/grid5000/sites/lyon/clusters/hydra/nodes/hydra-3.json

data/grid5000/sites/lyon/clusters/hydra/nodes/hydra-4.json

data/grid5000/sites/lyon/network_equipments/sneowise.json

input/grid5000/disks.yaml

input/grid5000/ipv4.yaml

input/grid5000/sites/lyon/clusters/hydra/hydra.yaml

input/grid5000/sites/lyon/clusters/hydra/nodes.yaml.erb

input/grid5000/sites/lyon/networks/sneowise.yaml

lib/refrepo/net_names_mapping.yaml