message: fix(test): remove illegal use of `bufferutils`
  The method `bufferutils.reverse` was removed a long time ago:
  It is unclear why this did not cause an error
  Issue:
diff: @@ -1812,7 +1812,7 @@ describe('Wallet API', function() {
  // parse tx to make sure the single key address was used to pay the fee
  const transaction = bitcoin.Transaction.fromHex(result.transactionHex);
  const singleKeyInput = transaction.ins[transaction.ins.length - 1];
  - const inputTxHash = bitcoin.bufferutils.reverse(singleKeyInput.hash).toString('hex');
  + const inputTxHash = Buffer.from(singleKeyInput.hash).reverse().toString('hex');
  // get the input tx to find the amount taken from the single key fee address
  return bitgo.get(bitgo.url('/tx/' + inputTxHash))
  