fix scalar bug

visualdl/logic/sdk.h

@@ -130,6 +130,8 @@ struct Scalar {
   void AddRecord(int id, T value) {
     auto record = tablet_.AddRecord();
     record.SetId(id);
+    time_t time = std::time(nullptr);
+    record.SetTimeStamp(time);
     auto entry = record.AddData<T>();
     entry.Set(value);
   }