The script does this:
function xts_as_tests {
echo "#-1. XTS AS Integration Test"
mvn -f ${WORKSPACE}/jboss-as/testsuite/integration/xts/pom.xml -Pxts.integration.tests.profile "$@" test
[ $? = 0 ] || fatal "XTS AS Integration Test failed"
}

Should probably be this:
function xts_as_tests {
echo "#-1. XTS AS Integration Test"
./build.sh -f ${WORKSPACE}/jboss-as/testsuite/integration/xts/pom.xml -Pxts.integration.tests.profile "$@" test
[ $? = 0 ] || fatal "XTS AS Integration Test failed"
}