Correct shared hash table rows estimation

[avamingli]

This is added by me, it's a thinko, at least not correct now.
ReplicatedWorkers path only has the data parallel workers should have.

The subpath's rows is set correctly no matter what locus it is.
Keep it with UPSTREAM.
For shared hash table size estimation, we need the total number, so we need to undo the division.

Authored-by: Zhang Mingli avamingli@gmail.com

closes: #ISSUE_Number

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LGTM