Summary:
`thread-id` is an Apple-defined key. `PushNotificationIOS.getDeliveredNotifications()` includes it, but the notification object currently ignores it. Since it's in the `aps` key, it's impossible to access without this change, as `getData()` does not include it.
Closes https://github.com/facebook/react-native/pull/17499
Differential Revision: D6696577
Pulled By: shergin
fbshipit-source-id: e0f48efd640bf5addb24a8d4352f9bb23f42612a
a8f429d3a8