curl --request POST \
  --url https://api.member.dev/api/v1/hub/{team_id}/hubs/{hub_id}/onboarding-attributes \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/vnd.api+json' \
  --data '
{
  "data": [
    {
      "attributes": {
        "definition_id": "<string>",
        "definition_slug": "<string>",
        "option_ids": [
          "<string>"
        ],
        "option_slugs": [
          "<string>"
        ],
        "value_boolean": true,
        "value_date": "2023-12-25",
        "value_number": 123,
        "value_text": "<string>"
      },
      "type": "<string>"
    }
  ]
}
'

{
  "data": [
    {
      "attributes": {
        "definition_id": "<string>",
        "definition_slug": "<string>",
        "type": "<string>",
        "option_ids": [
          "<string>"
        ],
        "option_slugs": [
          "<string>"
        ],
        "value_boolean": true,
        "value_date": "2023-12-25",
        "value_number": "<string>",
        "value_text": "<string>"
      },
      "id": "<string>",
      "type": "contact_attribute_values"
    }
  ]
}