Qemu: Set more default env variables in testrunner am: 6a181d347d

Original change: https://android-review.googlesource.com/c/platform/art/+/2977715

Change-Id: I4ca2bfd33babbe794a7afdc4ad17ee8333ed1f06
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>