bugfix：目录订阅收到更新事件时，sql字段update_time为空导致的报错

lishuyuan

2023-11-02 8bd2f47c9a92ffcf5ae43fae965eaefd4748e263

 src/main/java/com/genersoft/iot/vmp/gb28181/utils/SipUtils.java

@@ -261,6 +261,6 @@
                return null;
            }
        }
        return localDateTime.format(DateUtil.formatterISO8601);
        return localDateTime.format(DateUtil.formatter);
    }
}