getApproxHint: numTrials parameter overestimates required trials

[infalliblePirate]

In /bold/contracts/utils/hintExamples.js, the numTrials parameter in the call to HintHelper.getApproxHint is currently set as numTroves * 15. According to the function’s documentation, the intended formula is:

numTrials = k * sqrt(length), with k = 15

  // Get an approximate address hint from the deployed HintHelper contract. Use (15 * number of troves) trials
  // to get an approx. hint that is close to the right position.
  let numTroves = await sortedTroves.getSize();
  let numTrials = numTroves.mul(toBN("15"));
  let { 0: approxHint } = await hintHelpers.getApproxHint(NICR, numTrials, 42); // random seed of 42

Compute numTrials as 15 * sqrt(numTroves) instead of 15 * numTroves