Upgrade emulator to emu-master-dev build 8748233 am: 4ad9d9fb27 am: 2a1a95ce53

Original change: https://googleplex-android-review.googlesource.com/c/platform/prebuilts/android-emulator/+/19014779

Change-Id: Ic1ab7b791b1fa5727ad95e31be7230956d20ef6a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>