Fixing openonu-go-test pipeline to support voltha-2.6 patches

Change-Id: I884d67cea104f03dcd76a308ad12684f71a7a211
diff --git a/jjb/pipeline/voltha-bbsim-tests.groovy b/jjb/pipeline/voltha-bbsim-tests.groovy
index 65f1eac..226b7e7 100644
--- a/jjb/pipeline/voltha-bbsim-tests.groovy
+++ b/jjb/pipeline/voltha-bbsim-tests.groovy
@@ -33,7 +33,7 @@
     NAME="test"
     VOLTCONFIG="$HOME/.volt/config-$NAME"
     KUBECONFIG="$HOME/.kube/kind-config-voltha-$NAME"
-    EXTRA_HELM_FLAGS=" --set global.image_registry=mirror.registry.opennetworking.org/ "
+    EXTRA_HELM_FLAGS=" --set global.image_registry=mirror.registry.opennetworking.org/ --set defaults.image_registry=mirror.registry.opennetworking.org/ "
   }
 
   stages {