it('should encode height', () => {
  expect(HexEncoder.encodeHeight(0)).toStrictEqual('00000000')
  expect(HexEncoder.encodeHeight(1)).toStrictEqual('00000001')
  expect(HexEncoder.encodeHeight(255)).toStrictEqual('000000ff')
  expect(HexEncoder.encodeHeight(256)).toStrictEqual('00000100')