pgsql: docs: re-order some PG 16 relnotes items

docs: re-order some PG 16 relnotes items

Reported-by: Jonathan Katz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/07ef30a0282064f688a1923ba5e7c850f2ff5776

Modified Files
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doc/src/sgml/release-16.sgml | 66 ++++++++++++++++++++++----------------------
1 file changed, 33 insertions(+), 33 deletions(-)