Summary:
As part of #22609, this fixes yet more warnings.
- Adding more __unused to params.
- Refactors `isPackagerRunning` to use NSURLSession.
- Turns off suspicious comma warnings
[iOS] [Fixed] - Xcode Warnings
Pull Request resolved: https://github.com/facebook/react-native/pull/23565
Differential Revision: D14161151
Pulled By: cpojer
fbshipit-source-id: 339874711eca718fc6151e84737ccc975225d736
468ae234a6