removeAllConsent static method
Remove consent for all features. returns the error or success message
Implementation
static Future<String?> removeAllConsent() async {
  if (!_instance._countlyState.isInitialized) {
    String message = '"initWithConfig" must be called before "removeAllConsent"';
    log('removeAllConsent, $message', logLevel: LogLevel.ERROR);
    return message;
  }
  log('Calling "removeAllConsent"');
  final String? result = await _channel.invokeMethod('removeAllConsent');
  return result;
}