Fix errorprone warnings that should be errors am: 4d1c164550

Original change: https://android-review.googlesource.com/c/platform/external/testng/+/2256804

Change-Id: Ie15b049dbf0c3990765a4f4f83e2180852a1306e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>