Add VTS test for new observe mode command am: f046efb61b

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/3467744

Change-Id: Iaaaf3f838142599677eee029512f9de1d3a33fc4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>