Readability improvements in ApfTest. am: 3127123a93

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/2479596

Change-Id: I36938ed6815eaae6acf2a32d495057e2fea953b3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>