Change authenticationState to regular flow

Change authenticationState from conflatedCallbackFlow to regular
callbackFlow to prevent dropping values

Flag: NONE bug fix
Fixes: 355950083
Test: atest BiometricStatusRepositoryTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:51d4c66294c1d8eb6aff931d62fa784c0f277149)
Merged-In: I636eeec062801eba81cc123787430aaa8eb72f2c
Change-Id: I636eeec062801eba81cc123787430aaa8eb72f2c