[Backport] Remove stray reference to fix OOM while merging sketches (#13475)#13529

cryptoe merged 1 commit intoapache:25.0.0apache/druid:25.0.0from

adarshsanjeev:backport-sketch-merge-memory-fixadarshsanjeev/druid:backport-sketch-merge-memory-fixCopy head branch name to clipboard