sqrt method

Implementation

@override
FieldSqrtResult<Bls12NativeFp> sqrt() {
  final sqrt = pow(
    BigInt.parse(
      "1000602388805416848354447456433976039139220704984751971333014534031007912622709466110671907282253916009473568139947",
    ),
  );
  return FieldSqrtResult(sqrt, sqrt.square() == this);
}