message: test/bitgo: `buffer.length` instead of `byteLength`
  Not sure how `.byteLength` even worked since it's a method:
  In any case we care about `.length`
diff: @@ -18,7 +18,7 @@ const {
  describe('privateKeyBufferFromECPair', function () {
  it('pads short private keys', function () {
  var keyPair = new ECPair(BigInteger.ONE)
  - assert.strictEqual(privateKeyBufferFromECPair(keyPair).byteLength, 32)
  + assert.strictEqual(privateKeyBufferFromECPair(keyPair).length, 32)
  assert.strictEqual(privateKeyBufferFromECPair(keyPair).toString('hex'),
  '0000000000000000000000000000000000000000000000000000000000000001')
  })
  @@ -26,7 +26,7 @@ describe('privateKeyBufferFromECPair', function () {
  it('does not pad 32 bytes private keys', function () {
  var hexString = 'a000000000000000000000000000000000000000000000000000000000000000'
  var keyPair = new ECPair(new BigInteger(hexString, 16))
  - assert.strictEqual(privateKeyBufferFromECPair(keyPair).byteLength, 32)
  + assert.strictEqual(privateKeyBufferFromECPair(keyPair).length, 32)
  assert.strictEqual(privateKeyBufferFromECPair(keyPair).toString('hex'), hexString)
  })
  