code: public function addDevice($groupId, array $deviceIdentifiers)
      {
          $params = [
              'group_id' => intval($groupId),
              'device_identifiers' => $deviceIdentifiers,
          ];
  
          return $this->parseJSON('json', [self::API_ADD_DEVICE, $params]);
      }
docs: Add  one or more devices to a device group.
  
  @param int   $groupId
  @param array $deviceIdentifiers
  
  @return \EasyWeChat\Support\Collection