Comma separate co-opted accessibility labels (#52120)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52120

It is pretty jarring for semantically different labels to be read all at once, let's comma separate them - which VoiceOver will pause at. Android does this by default with its coopting implementation

Changelog: [Internal]

Reviewed By: jorge-cab

Differential Revision: D76921000

fbshipit-source-id: afe1f93e38babde918137576d0693c1579101ef7