Use openonu-py adapter chart version 2.4.6

Change-Id: Id552881dbe561941312dba64f6286154ee2d836a
diff --git a/releases/voltha-2.4 b/releases/voltha-2.4
index 71b0252..32ee212 100644
--- a/releases/voltha-2.4
+++ b/releases/voltha-2.4
@@ -6,7 +6,7 @@
 export VOLTHA_CHART_VERSION=2.5.6
 export VOLTHA_BBSIM_CHART_VERSION=3.1.0
 export VOLTHA_ADAPTER_OPEN_OLT_CHART_VERSION=2.5.8
-export VOLTHA_ADAPTER_OPEN_ONU_CHART_VERSION=2.4.5
+export VOLTHA_ADAPTER_OPEN_ONU_CHART_VERSION=2.4.6
 export ONOS_CLASSIC_CHART_VERSION=0.1.1
 export RADIUS_CHART_VERSION=1.0.1
 export VOLTCTL_VERSION=1.1.8