curl --request GET \
  --url https://example.com/api/scan/v0/top-validators-by-purchased-traffic

{
  "validatorsByPurchasedTraffic": [
    {
      "validator": "<string>",
      "numPurchases": 123,
      "totalTrafficPurchased": 123,
      "totalCcSpent": "<string>",
      "lastPurchasedInRound": 123
    }
  ]
}