pgsql: doc PG 17 relnotes: add item about libpq large data transfers

doc PG 17 relnotes: add item about libpq large data transfers

Reported-by: Jelte Fennema-Nio

Discussion: /messages/by-id/CAGECzQTz5aUqLEL6daLd2Hu2FXS_LOSh4keDndJ1fwThsb_b5w@mail.gmail.com

Reviewed-by: Joe Conway

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e87e7324555a93d7645e831209eee3404b9c05d3

Modified Files
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doc/src/sgml/release-17.sgml | 11 +++++++++++
1 file changed, 11 insertions(+)