Update an override shift

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

{
  "data": {
    "id": "ebbf7d24-3c84-4d27-b932-d983023b9c82",
    "type": "shifts",
    "attributes": {
      "schedule_id": "0756c216-66cb-41d3-ae11-9d27d89e64b3",
      "rotation_id": "6a8f4559-22d5-48da-af45-24e1b3cb8b9b",
      "starts_at": "2025-06-18T20:42:42.000-07:00",
      "ends_at": "2025-06-19T04:42:42.000-07:00",
      "is_override": true
    },
    "relationships": {
      "shift_override": {
        "data": {
          "id": "658a302b-0028-4900-9b44-80a780da78cc",
          "type": "shift_overrides"
        }
      },
      "user": {
        "data": {
          "id": "355",
          "type": "users"
        }
      }
    }
  }
}