make sure the buffer gets flushed.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@1838 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/scm/CVSSCM.java

@@ -837,6 +837,7 @@ public class CVSSCM extends AbstractCVSFamilySCM implements Serializable {
                 if(msg!=null)
                     w.println(msg);
                 e.printStackTrace(w);
+                w.close();
             }
         }