pgsql: docs: fix inconsistencies in markup and case

docs: fix inconsistencies in markup and case

Ensure to properly mark up function parameters in text with <parameter>,
avoid using <acronym> for terms which aren't acronyms and properly place
the ", and" in a value list. The acronym removal is a follow-up to commit
fb72a7b8c3 which removed it for minmax-multi.  In passing, also fix an
incorrectly cased word.

Author: Ekaterina Kiryanova <e.kiryanova@postgrespro.ru>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://postgr.es/m/c050ecbc-80b2-b360-3c1d-9fe6a6a11bb5@postgrespro.ru
Backpatch-through: v14

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9ffe128a6d616675b559a14a89f8b42a30084323

Modified Files
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doc/src/sgml/amcheck.sgml  | 4 ++--
doc/src/sgml/brin.sgml     | 2 +-
doc/src/sgml/catalogs.sgml | 4 ++--
doc/src/sgml/config.sgml   | 2 +-
4 files changed, 6 insertions(+), 6 deletions(-)