Merge "Unregister the tethering internal callback in finalize" am: f8d1f3d1cd am: c472eed19a am: 6236dfcb0d

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1838543

Change-Id: I472c50f3c6f52786b5b202dd79d0acd103bc09f4