setFixedEphemeral function
Test-only: the vector suites prescribe each party's ephemeral private key. Exported
from package:torann/testing.dart only; package:torann/torann.dart hides it, and
application code must not import testing.dart.
Implementation
Future<void> setFixedEphemeral(
HandshakeState handshake,
Uint8List privateKey,
) => hostCall(
() => hostApi.setFixedEphemeral(handshake._native.require(), privateKey),
);