[QS] Update string name in prep for freeze

Renaming the night light's "until <time>" string in case the translation
pipeline would re-register it after the freeze.

This is prepping for a change for the DnD secondary label.

Test: Visually/compiles
Bug: 70799372
Change-Id: I83608ce4dbf96c558b05191fc79f69325281e5b9