[DEPRECATED] Update an incident custom field selection

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

{
  "data": {
    "id": "1",
    "type": "incident_custom_field_selections",
    "attributes": {
      "custom_field_id": 173,
      "incident_id": "3a5d44f6-5ab1-4ae8-b363-5a460f3f1706",
      "value": "Test update custom field",
      "selected_option_ids": []
    }
  }
}