pgsql: doc: Fix some typos and grammar

doc: Fix some typos and grammar

This is a first batch of the fixes, for the most obvious fixes.  A
little bit more is under discussion.

Author: Thom Brown, Justin Pryzby
Discussion: https://postgr.es/m/CAA-aLv7xCZ0nBJa-NWe0rxBB28TjFjS2JtjiZMoQ+0wsugG+hQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/644b848f50ef75430c0134654f86e8234691e390

Modified Files
--------------
doc/src/sgml/archive-modules.sgml        | 6 +++---
doc/src/sgml/client-auth.sgml            | 6 +++---
doc/src/sgml/indexam.sgml                | 2 +-
doc/src/sgml/install-windows.sgml        | 2 +-
doc/src/sgml/logicaldecoding.sgml        | 2 +-
doc/src/sgml/pgbuffercache.sgml          | 2 +-
doc/src/sgml/postgres-fdw.sgml           | 6 +++---
doc/src/sgml/ref/create_publication.sgml | 2 +-
doc/src/sgml/ref/createuser.sgml         | 4 ++--
doc/src/sgml/ref/pg_waldump.sgml         | 2 +-
doc/src/sgml/ref/psql-ref.sgml           | 7 +++----
doc/src/sgml/ref/reindex.sgml            | 2 +-
12 files changed, 21 insertions(+), 22 deletions(-)