/lu/dev(fennel): fix problem where the scratch buffer pages used by partition writers of LhxAggExecStream are released too early, and invalid data is being written to the writer hash table.(LER3943).
/lu/dev(fennel): fix problem where the scratch buffer pages used by partition writers of LhxAggExecStream are released too early, and invalid data is being written to the writer hash table.(LER3943).

[git-p4: depot-paths = "//open/lu/dev/": change = 8628]

LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb