Don't show scrambler checker box when the competitor's nationalRanking equals 0

[maxidragon]

This will happen if the competitor switches nationality and haven't achieved PRs under new country yet, see example

{
  "name": "Axel Morley",
  "wcaUserId": 186124,
  "wcaId": "2022MORL01",
  "registrantId": 19,
  "countryIso2": "FR",
  "gender": "m",
  "personalBests": [
    {
      "eventId": "333oh",
      "best": 2178,
      "worldRanking": 9967,
      "continentalRanking": 2567,
      "nationalRanking": 0,
      "type": "average"
    }
  ]
}