2939 - Fix filter in group query

xivo_dao/resources/agent/dao.py

@@ -78,6 +78,6 @@ def get_membership(agent_id):
 
 def get_group_by_id(group_id):
     query = (Session.query(AgentGroup)
-             .filter(id=group_id))
+             .filter(AgentGroup.id == group_id))
 
     return query.first()