Fix DK 8 and Scala 2.11 failure reported by Jenkin?

[Ming Liu]

Hey,
   I have a simple PR https://github.com/apache/kafka/pull/5989/files, it
always failed for JDK 8 and Scala 2.11 in jenkin build. I have been trying
to repro with the local build (like ./gradlew -PscalaVersion=2.12 test or
set Java_HOME etc), but it always build and test successfully for me
locally.

  Anybody has a good idea how to repro that failure locally?

 Thanks!
 Ming