LUCI: Add 'product' property for qemu builds am: 948a48aa04 am: 18e2abfaf7

Original change: https://android-review.googlesource.com/c/platform/art/+/2982192

Change-Id: Ic8f0b243c54b950d4a497f41891785221efd441f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>