Always hide alternate bouncer if it's showing & device unlocked

Also make sure to stay on the current scene if the alternate
bouncer was showing when the device was unlocked if
the shade should continue showing.

The AlternateBouncer isn't it's own scene,
so hiding it is sufficient on
unlocked to show the desired UI when the shade should
be kept open (this differs being unlocked from
the primary bouncer since the primary bouncer is its
own scene).

Bug: 353955910
Flag: com.android.systemui.scene_container
Test: with SFPS enrolled, pull down QS over
the lockscreen and tap on the "edit" icon. Authenticate
with SFPS from the alternate bouncer and observe the device
stays on the quick settings scene with the "Edit QS" UI
showing.
Test: atest SceneContainerStartableTest

Change-Id: I61d6982cec4b70452aa43490227ec21b45f61140