doc: Improve PG14 release notes

Bruce Momjian <bruce@momjian.us>

Commit: caa0f07d2d4b69cd53b5bf7c847d9d65eadbbfee
Author: Bruce Momjian <bruce@momjian.us>
Date: 2021-06-29T00:58:47Z
Releases: 14.0
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

Files

PathChange+/−
doc/src/sgml/release-14.sgml modified +43 −34

Documentation touched