regenerate reference api

data/grid5000/sites/nantes/servers/srv-3.json

+{
+  "alias": [
+    "ntp"
+  ],
+  "kind": "physical",
+  "network_adapters": {
+    "bmc": {
+      "ip": "172.17.207.4",
+      "mac": "4c:d9:8f:34:f8:7e"
+    },
+    "default": {
+      "ip": "172.16.207.4",
+      "mac": "e4:43:4b:69:74:22"
+    }
+  },
+  "serial": "9TJRXW2",
+  "type": "server",
+  "uid": "srv-3",
+  "warranty": "2019-11"
+}
\ No newline at end of file

data/grid5000/sites/nantes/servers/srv-4.json

+{
+  "alias": [
+    "ntp"
+  ],
+  "kind": "physical",
+  "network_adapters": {
+    "bmc": {
+      "ip": "172.17.207.5",
+      "mac": "4c:d9:8f:34:f9:f2"
+    },
+    "default": {
+      "ip": "172.16.207.5",
+      "mac": "e4:43:4b:68:bf:30"
+    }
+  },
+  "serial": "BTJRXW2",
+  "type": "server",
+  "uid": "srv-4",
+  "warranty": "2019-11"
+}
\ No newline at end of file