Merge "Lock ATV UI mode to prevent Car Mode tests from running + failing" into rvc-dev am: 685aa0c201 am: 920aed4281

Original change: https://googleplex-android-review.googlesource.com/c/device/google/atv/+/11757266

Change-Id: I4e8d0f51f351ae354ccfa2bdc53352cd3366e6c0