pgsql: doc: PG 16 relnotes: fix spelling error

doc: PG 16 relnotes: fix spelling error

Reported-by: Lele Gaifax

Discussion: /messages/by-id/87cyximsps.fsf@metapensiero.it

Backpatch-through: 16 only

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/418d6b4430a5dbfbe4dd9c10ada367f0aee88b52

Modified Files
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doc/src/sgml/release-16.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)