Merge "Fix lint and errorprone warnings in FakeDns." into main am: c29fbe7777

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/3256497

Change-Id: Ia0a23d4611016cce8260a49c6c3a010ea756cea5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>