Some tests are not cleanly using the target folder (creating targetfoo instead of target/foo) (#1531)

Author: jbonofre

activemq-broker/pom.xml

@@ -187,7 +187,7 @@
           <argLine>${surefire.argLine}</argLine>
           <runOrder>alphabetical</runOrder>
           <systemPropertyVariables>
-            <org.apache.activemq.default.directory.prefix>target</org.apache.activemq.default.directory.prefix>
+            <org.apache.activemq.default.directory.prefix>target/</org.apache.activemq.default.directory.prefix>
           </systemPropertyVariables>
           <includes>
             <include>**/*Test.*</include>