Fix rotate device at face unlock detailed page, device will display

redundant face unlock header.

1. Change the FaceSettings theme style to avoid an action bar
appearing.
2. In AndroidManifest.xml to apply configChanges attribute for
handling device orientation.

Bug: 262497152

Test: manually to do reproduced steps:
Pre-Condition:
1. enroll face
2. enable auto rotate

Procedure:
1.go to settings > security > face & fingerprint unlock
2.enter screen lock
3.click face unlock
4.rotate device into landscape mode and then back to portrait mode
5.check the UI

Test: make RunSettingsRoboTests ROBOTEST_FILTER="com.android.settings
.biometrics.face.FaceSettingsActivityTest"

Change-Id: I4ee1bb4f061ea2d141043405213ba6e60bacd92f