Update workflows in preference set

Example response

{
  "categories": {
    "marketing": false,
    "transactional": {
      "channel_types": {
        "email": false
      }
    }
  },
  "channel_types": {
    "email": true,
    "push": false,
    "sms": {
      "conditions": [
        {
          "argument": "US",
          "operator": "equal_to",
          "variable": "recipient.country_code"
        }
      ]
    }
  },
  "commercial_subscribed": true,
  "id": "default",
  "workflows": null
}