fix bug

models/data_source_longzhong.go

@@ -647,7 +647,7 @@ func ModifLongzhongSurveyProductCode(lzCode string, surveyProductId int) (err er
 	o := orm.NewOrm()
 	o.Using("edb")
 	sql := `UPDATE  longzhong_survey_product
-			SET lz_code= ?
+			SET lz_code= ?,modify_time=NOW()
 			WHERE survey_product_id = ? `
 	_, err = o.Raw(sql, lzCode, surveyProductId).Exec()
 	return