Add test for tetherOffloadRule4Clear am: fa3942c7e7 am: 82d3838d8c am: f97928387b

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

Change-Id: Ic802062619c16f3421f12cbb096b9a568cdbe330
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>