pgsql: doc: change "cross product" to "Cartesian product"

doc: change "cross product" to "Cartesian product"

Reported-by: Erik Wienhold

Discussion: /messages/by-id/2053109544.160895.1684955437950@office.mailbox.org

Author: Erik Wienhold

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8438a3ffef283d12b387eeb73616809e4c409483

Modified Files
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doc/src/sgml/queries.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)