BitShufflePageDecoder reuses the memory for storing decoder results, allocate memory directly from the
`ChunkAllocator`, the performance is improved to a certain extent.
In the case of #6285, the total time consumption is reduced by 13.5%, and the time consumption ratio of `~Reader()`
has also been reduced from 17.65% to 1.53%, and the memory allocation is unified to `ChunkAllocator` for centralized
management , Which is conducive to subsequent memory optimization.
which can avoid the memory waste caused by `Mempool`, because the chunk can be free at any time, but the
performance is lower than the allocation from `Mempool`. The guess is that there is no `Mempool` after secondary
allocation of large chunks , Will directly apply for a large number of small chunks from `ChunkAllocator`, and it takes
longer to lock in `pop_free_chunk` and `push_free_chunk` (but this is not proven from the flame graphs of BE's cpu and
contention).
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