Add logs to onClientIdSet() when push or context is not available

[KacperKluka]

As noticed here we are only handling the happy-path in the onClientIdSet() in AblyRest and AblyRealtime classes in ably-android module. We should also handle a scenario when either push or the applicationContext is null. At least we should log an appropriate message to the log handler.

┆Issue is synchronized with this Jira Task by Unito