Merge "Add test for CSM#[get|set]MobileDataPreferredUids" am: 5440e0b8e8 am: 732ab7557c

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1736504

Change-Id: I0176debea776e1ed6473cc52d44160576665db2b