Fix errorprone warnings that should be errors am: 6aa0b94839 am: b7bfec8510

Original change: https://android-review.googlesource.com/c/platform/test/mlts/benchmark/+/2254751

Change-Id: I058d91f19d5e0c6f0415b9e3fd312b5ca4de8d81
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>