feat(bluetooth-le): Allow specifying transport mode for Android

[EinfachHans]

See merged PR: https://github.com/randdusing/cordova-plugin-bluetoothle/pull/647/files

[p-andreas]

Thanks for raising this PR.

Until it is accepted I use the following workaround:

   const connectionParams = {
      address: deviceAddress,
      transport: 2, // required until https://github.com/ionic-team/ionic-native/pull/3571 is merged
      // magic value 2 is AndroidGattTransportMode TRANSPORT_LE
    } as {
      address: string;
      autoConnect?: boolean;
    };

  this.bluetooth.connect(connectionParams).subscribe( /* do something meaningful */);