[Screen off unlock UDFPS] Settings integration 1/2

1. Add a settings key SCREEN_OFF_UNLOCK_UDFPS_ENABLED
2. Integrate the key to AmbientDisplayConfiguration.java

Bug: 373792870
Bug: 369939804
Bug: 369938501
Flag: android.hardware.biometrics.screen_off_unlock_udfps
Test: atest DozeSensorsTest
Test: adb shell settings put secure
      screen_off_unlock_udfps <1|0>
Change-Id: If3655a0492469d5048c87c0e032d678c2e764393