With bellow json path
`["$.data","$.data.datatimestamp"]`
After `array_obj->PushBack` the `data` field owner will be taken from array_obj, and lead to null values for json path `$.data.datatimestamp`
Rapidjson doc:
```
//! Append a GenericValue at the end of the array.
\note The ownership of \c value will be transferred to this array on success.
*/
GenericValue& PushBack(GenericValue& value, Allocator& allocator);
```
