Change face auth trigger to LockScreen -> Shade transition

It was incorrectly set to QuickSettings -> Shade in the previous CL

Other changes:
 Address unresolved comment from previous CL ag/28949039 (transition to GONE instead of UNDEFINED)

Bug: 361673279
Test: atest DeviceEntryFaceAuthInteractorTest
Test: manually,
 1. enroll face auth
 2. start pulling down the shade
 4. face auth should run without affecting the shade expansion
Flag: com.android.systemui.scene_container
Change-Id: I17eed5065fa6f7f2d24b2b18a4dd60b70c682a35