Fix issue with some resource types not updating (eg. 'hostgroup').

[stana]

For update api PUT requests, Foreman is expecting params to be sent inside 'resource type' dict (similar to 'create'). For example -

{
  "id": <resource id>,
  "<resource type>": {
    "param1": "value",
    "param2": "value",
    ...
    "paramN": "value"
  }
}