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/conf/MediaConfig.java

@@ -233,5 +233,4 @@
        }
        return false;
    }

}