Merge "Quit handler threads at the end of the tests" into main am: 006f9d2998

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2812073

Change-Id: Ib7dadbd9c892781ceb96399e50f456d3cd29c9df
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>