Using dev image for BBSim in scale test

Change-Id: I42b7a812bdb6ecc5816973870aef7a9a8d318772
diff --git a/jjb/voltha-scale.yaml b/jjb/voltha-scale.yaml
index c1904ea..cf88246 100644
--- a/jjb/voltha-scale.yaml
+++ b/jjb/voltha-scale.yaml
@@ -71,7 +71,7 @@
           openoltAdapterImg:  gcgirish/voltha-openolt-adapter:flowChanPerSub
           rwCoreImg: matteoscandolo/voltha-rw-core:sync-delete
           radiusChart: /home/cord/helm-charts/freeradius
-
+          bbsimImg: matteoscandolo/bbsim:nni-packet-logs
 
       # jobs for 512 ONUs with a 8 openonu-adapters and clustered ONOS (1 OLT)
       - 'voltha-scale-measurements':