All a11y actions on lock icon should go to the bouncer

Modify messaging to make it clear that the user is going to the device
entry screen. In Talkback, the user will now hear "device locked.
double tap to enter screen lock".

Any time the a11y user interacts with any udfps or non-udfps lock icon,
they should be taken to the bouncer.

Fixes: 344493721
Test: atest DeviceEntryIconViewModelTest
Flag: com.android.systemui.device_entry_udfps_refactor
Change-Id: I8bd268fc350326150c25fc4f9ef4f2672c16a30f