Do not wait for adapter in VOLTHA 2.8, only wait 5 minutes before force-removing ONOS

Change-Id: Ie1d90eeaecf4201f3ebb6734080a2b89337faeb7
diff --git a/jjb/pipeline/voltha/master/voltha-scale-test.groovy b/jjb/pipeline/voltha/master/voltha-scale-test.groovy
index 0727840..91d5552 100644
--- a/jjb/pipeline/voltha/master/voltha-scale-test.groovy
+++ b/jjb/pipeline/voltha/master/voltha-scale-test.groovy
@@ -59,7 +59,7 @@
       steps {
         script {
           try {
-            timeout(time: 10, unit: 'MINUTES') {
+            timeout(time: 5, unit: 'MINUTES') {
               sh returnStdout: false, script: '''
               cd $WORKSPACE
               rm -rf $WORKSPACE/*