Adding group_id for kafka client

Change-Id: I7cacdc8474108f65ad21ea0b47c957e87ccceb3e
Signed-off-by: Eduardo Sousa <esousa@whitestack.com>
diff --git a/osm_nbi/nbi.cfg b/osm_nbi/nbi.cfg
index e206522..d22f8fd 100644
--- a/osm_nbi/nbi.cfg
+++ b/osm_nbi/nbi.cfg
@@ -86,6 +86,7 @@
 
 loglevel:  "DEBUG"
 #logfile: /var/log/osm/nbi-message.log
+group_id: "nbi-server"
 
 [authentication]
 backend: "internal"