LOG4J2-75 Prevent JUnit test from creating unnecessary Log4j2Plugins.dat file during build.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1614908 13f79535-47bb-0310-9956-ffa450edef68
fixed wrong ID for previous changes

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1614909 13f79535-47bb-0310-9956-ffa450edef68