setSymKey method
Implementation
@override
Future<String> setSymKey(String symKey, {String? overrideTopic}) async {
_checkInitialized();
final String topic = overrideTopic ?? utils.hashKey(symKey);
// print('crypto setSymKey, symKey: $symKey, overrideTopic: $topic');
await keyChain.set(topic, symKey);
return topic;
}