Update RetrospectiveProcessGroup Step

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

{
  "data": {
    "id": "0d2b7446-4406-47c0-bc84-1f8aa00934df",
    "type": "retrospective_process_group_steps",
    "attributes": {
      "retrospective_process_group_id": "d557109a-d8fd-4517-ad82-0acee880490d",
      "retrospective_step_id": "e712b6e9-ddea-4074-9903-3e1e687a7f04",
      "position": 2,
      "updated_at": "2025-10-30T04:15:14.380-07:00",
      "created_at": "2025-10-30T04:15:14.314-07:00"
    }
  }
}