Add test for tetherOffloadRule4Clear am: fa3942c7e7 am: 5b3fe8dc7c

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1838894

Change-Id: Ia36b18bea58862498c571e9f7b3875d70e54f571
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>