start method
Implementation
@override
Future<String?> start(String apyKey,
[num? consentPreferenceValidityDays]) async {
eventChannel.receiveBroadcastStream().listen(_onEvent, onError: _onError);
final started = await methodChannel.invokeMethod<String>('start', {
'apiKey': apyKey,
'consentPreferenceValidityDays': consentPreferenceValidityDays
});
return started;
}