register method
Creates and sends a new one-time passcode for registration.
Parameters:
identifier: The Passage User's identifier.language: The language code for the one time passcode.
Returns:
A Future<OneTimePasscode> that returns a one-time passcode ID used to activate
the passcode in oneTimePasscodeActivate.
Throws:
PassageError
Implementation
Future<OneTimePasscode> register(String identifier, {String? language}) async {
String oneTimePasscodeId = await PassageFlutterPlatform.instance
.newRegisterOneTimePasscode(identifier, language);
return OneTimePasscode(oneTimePasscodeId);
}