Add callback to check biometric prompt status on keyguard

Use BiometricManager#registerBiometricPromptStatusListener(IBiometricPromptStatusListener
listener) to register a callback. When authenticate is requested by
an app, callback.onBiometricPromptShowing() will be called
and once the biometric prompt is dismissed,
callback.onBiometricPromptIdle() will be called.

Bug: 302141167
Test: atest BiometricServiceTest

Change-Id: I4dce56c71be8c80246a9da7d5f4800ff4b9713f8