Always enabling persistency on AWS based scale job

Change-Id: If01113999b1127c117819ab9d6302270a81ee21e
diff --git a/jjb/voltha-scale.yaml b/jjb/voltha-scale.yaml
index 801364f..085b216 100644
--- a/jjb/voltha-scale.yaml
+++ b/jjb/voltha-scale.yaml
@@ -63,6 +63,7 @@
           withEapol: true
           withDhcp: true
           withIgmp: false
+          inMemoryEtcdStorage: false
           extraHelmFlags: '--set authRetry=true,dhcpRetry=true --set global.log_correlation.enabled=true -f /home/jenkins/voltha-scale/voltha-values.yaml --set etcd.persistence.enabled=true,etcd.persistence.storageClass=longhorn'
           onosImg: andreacampanella/voltha-onos:voltha-onos-2.5
           bbsimImg: gcgirish/bbsim:etcd