[IMP] Decrease Merge Peak Memory Usage of ConnectedComponents

[VibhuJawa]

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Describe the bug

On smaller GPU skews we are running into memory issues in the broadcast merge in Connected Components. We have to decrease that memory footprint without hurting performance too much.

https://github.com/NVIDIA/NeMo-Curator/blob/f7441ea19df3200067545f630472fa937f285d86/nemo_curator/modules/fuzzy_dedup.py#L1605-L1655

CC: @ayushdg