add apple privacy manifest & usage descriptions for UserDefaults

[johnhatvani]

Summary

#830

Starting May 1, Apple will enforce 3rd party SDK's to sign & provide privacy manifests for specific API's being accessed by the code. This change adds a privacy manifest and reason for using the data. Apple Documentation

I have added a declaration for use of UserDefualts via NSPrivacyAccessedAPICategoryUserDefaults and from reading the code have stated the reason

CA92.1
Declare this reason to access user defaults to read and write information that is only accessible to the app itself.

This reason does not permit reading information that was written by other apps or the system, or writing information that can be accessed by other apps.

Test Plan

What's required for testing (prerequisites)?

Build and run the example app

What are the steps to test it (after prerequisites)?

Upon building the IPA you can inspect the IPA and find RNPermissions_PrivacyInfo.bundle and within that find PrivacyInfo.xcprivacy

Compatibility

OS	Implemented
iOS	✅
Android	❌

Checklist

• I have tested this on a device and a simulator
• I added the documentation in README.md
• I added a sample use of the API in the example project (example/App.tsx)

Notes

• iOS Only
• No changes required to documentation
• No additions required for the example project

[zoontek]

@johnhatvani Thanks! I merge that in a separate branch as it's still need a bit of work (ideally, we want to add the manifest only if the concerned permission is used: FaceID)

Then I will do a release.

[johnhatvani]

@zoontek Thanks! I'm not sure that the manifests are conditional like that, unless you have seen something different?

[zoontek]

@johnhatvani I updated the setup script to conditionally comment / uncomment the line: https://github.com/zoontek/react-native-permissions/blob/master/scripts/setup.rb

[johnhatvani]

nice change! was wondering how you would achieve that 🙏🏼 -- will that code be omitted if the end-user does not use FaceID? - I would assume that the scanner apple have won't look for when a particular API is utilised, only scan the binary for the symbol being present in the code