Recycle buffers to freeSegments before releasing data buffer for sort accumulator

When using sortBufferAccumulator, we should recycle the buffers to freeSegments before releasing the data buffer. The reason is that when getting buffers from the DataBuffer, it may require more buffers than the current quantity available in freeSegments. Consequently, to ensure adequate buffers from DataBuffer, the flushed and recycled buffers should also be added to freeSegments for reuse.