Обсуждение: pgsql: doc: Improve PG14 release notes

doc:  Improve PG14 release notes

Mostly markup improvements.

Reported-by: Justin Pryzby

Discussion: https://postgr.es/m/20210625230456.GP29179@telsasoft.com

Backpatch-through: 14 only

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/caa0f07d2d4b69cd53b5bf7c847d9d65eadbbfee

Modified Files
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doc/src/sgml/release-14.sgml | 77 +++++++++++++++++++++++++-------------------
1 file changed, 43 insertions(+), 34 deletions(-)