[ONOS-6901] Fix how the systemTest does not return any result when it forced to quit the test

Change-Id: If93c48d46e8dc2494046b42de21f732775d7f520
diff --git a/TestON/tests/USECASE/VPLS/VPLSBasic/VPLSBasic.py b/TestON/tests/USECASE/VPLS/VPLSBasic/VPLSBasic.py
index 0b8c85d..d0f4ed7 100644
--- a/TestON/tests/USECASE/VPLS/VPLSBasic/VPLSBasic.py
+++ b/TestON/tests/USECASE/VPLS/VPLSBasic/VPLSBasic.py
@@ -56,7 +56,7 @@
             main.testSetUp = ONOSSetup()
         except ImportError:
             main.log.error( "ONOSSetup not found. exiting the test" )
-            main.exit()
+            main.cleanAndExit()
         main.testSetUp.envSetupDescription()
         stepResult = main.FALSE
         try: