Build failure in Jenkins build of log4j/master (18)

[Apache Jenkins Server]

There is a build failure in log4j/master.

Build: https://builds.apache.org/job/log4j/job/master/18/
Logs: https://builds.apache.org/job/log4j/job/master/18/console
Changes: https://builds.apache.org/job/log4j/job/master/18/changes