[QS] Change secondary label for night light

If the night light is scheduled and the minute reading is 0, we'll
continue showing just the hour. But for non-zero minute schedules, we'll
show "hour:minutes" instead.

Test: visually
Bug:69973398
Change-Id: Ida78aa0b872b7f8b6f8cd84fa559ff44c71175cd
1 file changed