VOL-2686 Configure multicast MEs when flows are pushed and tp is configured

Change-Id: I283d6e689c010ec7e9c45c5921a20e08f3d5a93c
diff --git a/python/requirements.txt b/python/requirements.txt
index f35a394..3cab263 100644
--- a/python/requirements.txt
+++ b/python/requirements.txt
@@ -1,2 +1,2 @@
 voltha-protos==3.2.6
-pyvoltha==2.3.20
+pyvoltha==2.3.21