Update brightness sensor registration on AOD_PAUSED changes

So that the binned brightness sensor immediately updates
the brightness rather than using its 2-3 second debouncing logic.
This prevents a delay in reporting brightness updates when the
device's proximity sensor stops being covered.

Test: atest DozeScreenBrightnessTest
Fixes: 200768925
Change-Id: Ib1158894d4f7b303247feacd24664f628663d733