Allocate pseudo tty for ssh

Change-Id: I43e977ce5099b9d593e3e36bd6f2a0f540b54419
diff --git a/tools/test/bin/onos-uninstall b/tools/test/bin/onos-uninstall
index e2a2816..84db340 100755
--- a/tools/test/bin/onos-uninstall
+++ b/tools/test/bin/onos-uninstall
@@ -8,7 +8,7 @@
 
 remote=$ONOS_USER@${1:-$OCI}
 
-ssh $remote "
+ssh -t $remote "
     sudo service onos stop 1>/dev/null 2>/dev/null
     sudo rm -fr $ONOS_INSTALL_DIR
 "