Add strings for active unlock in settings

Add strings that active unlock needs to consume when surfacing itself in
combined biometrics settings.

Test: none, strings aren't consumed yet.
Bug: 266583888
Bug: 240437016
Change-Id: I41e3b9c1830212303fc3379462e80cb18a23d026
Merged-In: I41e3b9c1830212303fc3379462e80cb18a23d026