run-single-test should write TEST-*.xml to the correct place.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@432720 13f79535-47bb-0310-9956-ffa450edef68

build.xml

@@ -1757,7 +1757,7 @@
      depends="test-init">
     <test-junit >
       <formatter type="plain" usefile="false"/>
-      <test name="${testcase}"/>
+      <test name="${testcase}" todir="${build.tests.xml}"/>
     </test-junit>
   </target>