Update a FormFieldPosition

curl --request PUT \
  --url https://api.rootly.com/v1/form_field_positions/{id} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/vnd.api+json' \
  --data '{
  "data": {
    "type": "form_field_positions",
    "attributes": {
      "form_field_id": "<string>",
      "form": "web_new_incident_form",
      "position": 123
    }
  }
}'

{
  "data": {
    "id": "0a0b705d-a85a-46c6-9fe3-909bcf544741",
    "type": "form_field_positions",
    "attributes": {
      "form_field_id": "54b5f10d-9083-4547-a4af-6fb7755465d1",
      "form": "slack_update_incident_form",
      "position": 2
    }
  }
}