ovn-northd: Fix unknown table "port_group_set" warning.

_DUMP_DB_TABLES macro should instead dump "port_group" table.

Fixes: 5b6a7ad ("northd: Add incremental processing for NB port groups.")
Acked-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Numan Siddique <numans@ovn.org>

tests/ovn-northd.at

@@ -11,7 +11,7 @@ m4_define([_DUMP_DB_TABLES], [
     ovn-sbctl list address_set >> $1
     ovn-sbctl list meter >> $1
     ovn-sbctl list meter_band >> $1
-    ovn-sbctl list port_group_set >> $1
+    ovn-sbctl list port_group >> $1
 ])
 
 # CHECK_NO_CHANGE_AFTER_RECOMPUTE