video expectations: Supress hevc_main_part_3 on Cherry

Since a few test vectors are failing and fixing those is expected
to take a long time.

BUG=b:352514619
TEST=Error is suppressed on cherry with this yml copied by hand.

Change-Id: Ic18247caa8ae0929df3e9b7b43986c55b6898a8a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/graphics/+/5696529
Tested-by: Miguel Casas-Sanchez <mcasas@chromium.org>
Auto-Submit: Miguel Casas-Sanchez <mcasas@chromium.org>
Reviewed-by: Steve Cho <stevecho@chromium.org>
Commit-Queue: Steve Cho <stevecho@chromium.org>