Fix tethering unit test fail in R am: 9eac605333 am: b582c81ee8 am: 52998bed1d am: a4578b20ec

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1711436

Change-Id: I2db19d5989a9672a0e677a5ba7af61b059b20f9f