[VTS] Update SetDisplayBrightness test item am: 70d2ef6b34

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2883951

Change-Id: I88bbe947e893f2914d5ec93c169d9ca252fda697
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>