[Provider Model] Refactor AirplaneSafeNetworksSliceTest

- The AirplaneSafeNetworksSliceTest should restore Airplane Mode state
after tear down

- Create AirplaneModeRule to backup/restore Airplane Mode state
automaticlly

- Plan to reuse the AirplaneModeRule for other test case

Bug: 173413889
Test: atest -c AirplaneSafeNetworksSliceTest
Change-Id: Id142cf6302a188e6d82b44fcf29a395dc21f6013