[lyon][test] Describe a fake cluster named 'test'

data/grid5000/accesses/refrepo.json

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

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

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

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

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

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

input/grid5000/ipv4.yaml

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

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

input/grid5000/sites/lyon/networks/gw-lyon.yaml