Обсуждение: pgsql: doc: PG 16 relnotes, add links to doc sections

doc:  PG 16 relnotes, add links to doc sections

Backpatch-through: 16 only

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/11f4935490eb8597fcc0e3e71c2caf90e6154943

Modified Files
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doc/src/sgml/release-16.sgml | 354 +++++++++++++++++++++----------------------
1 file changed, 176 insertions(+), 178 deletions(-)