fix wrong name

Author: RogerKSI

flusher/flusher/db.py

@@ -515,7 +515,7 @@ def Column(*args, **kwargs):
     "group_policies",
     metadata,
     Column("address", sa.String, primary_key=True),
-    Column("types", sa.String),
+    Column("type", sa.String),
     Column("group_id", sa.Integer, sa.ForeignKey("groups.id")),
     Column("admin", sa.String, sa.ForeignKey("accounts.address")),
     Column("metadata", sa.String),