RN: Delete `@oncall` Annotations (#51416)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/51416

Deletes `oncall` annotations from the `facebook/react-native` repository.

Changelog:
[Internal]

Reviewed By: javache

Differential Revision: D74902524

fbshipit-source-id: 32a6a5b2ff27281792d572f151e2b094d9a79029