performance improvement: reduced test running time from 13 seconds to 3 seconds

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595453 13f79535-47bb-0310-9956-ffa450edef68
performance improvement of SyslogAppenderTest and TLSSyslogAppenderTest: decreased running time by 3 seconds

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595468 13f79535-47bb-0310-9956-ffa450edef68