Check pending queue for cancelAuthentication

If cancelAuthentication is requested but actual authentication
has not started yet (e.g. a previous non-cancelable operation such
as updateActiveGroup or getAuthenticatorId is still running), look
through the pending queue and mark all matched authentication clients
as STATE_WAITING_IN_QUEUE_CANCELING.

Test: atest BiometricSchedulerTest
Fixes: 178105328
Change-Id: I755359adbdcda7f054135a190426b4a78a7a5125