pgsql: Fix costing for disk-based hash aggregation.

Fix costing for disk-based hash aggregation.

Report and suggestions from Richard Guo and Tomas Vondra.

Discussion: https://postgr.es/m/CAMbWs4_W8fYbAn8KxgidAaZHON_Oo08OYn9ze=7remJymLqo5g@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7351bfeda33b60b69c15791c7eb77a127546df26

Modified Files
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src/backend/executor/nodeAgg.c        |  2 ++
src/backend/optimizer/path/costsize.c | 30 ++++++++++++++----------------
2 files changed, 16 insertions(+), 16 deletions(-)