Controller type displays as "Undefined"

Where was this behaviour seen? Might need to see the websocket response in the console for this.

My assumption is this is caused by the data not being correctly populated by `websockets.handlers.node:NodeHandler.dehydrate`, but that will need a little more testing.

You can see this on the controller listing page, under the "Type" column. Each item shows as "undefined" instead of the actual type of the controller. As for the websocket response:

{
    "type": 1,
    "request_id": 5,
    "rtype": 0,
    "result": [
        {
            "id": 1,
            "system_id": "xf64c7",
            "hostname": "NICKDV-UBUNTU",
            "domain": {
                "id": 0,
                "name": "maas"
            },
            "status": "Deployed",
            "node_type": 4,
            "cpu_count": 24,
            "cpu_speed": 4672,
            "last_image_sync": "Wed, 11 Jan. 2023 16:44:43",
            "permissions": [
                "edit",
                "delete"
            ],
            "fqdn": "NICKDV-UBUNTU.maas",
            "actions": [
                "set-zone",
                "import-images",
                "delete"
            ],
            "link_type": "controller",
            "tags": [],
            "architecture": "amd64/generic",
            "osystem": "ubuntu",
            "distro_series": "kinetic",
            "memory": 32,
            "description": "",
            "status_code": 6,
            "simple_status": "Deployed",
            "vlans_ha": {
                "true": 0,
                "false": 6
            },
            "versions": {
                "install_type": "snap",
                "current": {
                    "version": "3.4.0~alpha1-13430-g.b872597ef",
                    "snap_revision": "25522"
                },
                "origin": "latest/edge",
                "up_to_date": true,
                "issues": []
            },
            "service_ids": [
                1,
                2,
                3,
                4,
                5,
                6,
                7,
                8,
                9,
                10,
                11,
                12,
                13,
                14,
                15
            ],
            "vault_configured": false
        }
    ]
}

`node_type` is being sent, however `node_type_display` is not. I believe its removal is due to the ongoing "faster machine list" spike. Theoretically this could be fixed in the frontend so as not to impede progress on the spike, we do have a util for fetching the display type based on just the `node_type` value. Ultimately depends what the rest of the team would rather do.