pgsql: Doc: Improve wording of multiple places in documentation

Doc: Improve wording of multiple places in documentation

This has been found during its translation.

Author: Liudmila Mantrova
Discussion: /messages/by-id/CAEkD-mDJHV3bhgezu3MUafJLoAKsOOT86+wHukKU8_NeiJYhLQ@mail.gmail.com
Backpatch-through: 12

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/0431a787469265776eeb9a472beb3457d2990edb

Modified Files
--------------
doc/src/sgml/catalogs.sgml | 20 ++++++-------
doc/src/sgml/client-auth.sgml | 9 +++---
doc/src/sgml/config.sgml | 29 +++++++++---------
doc/src/sgml/ecpg.sgml | 60 ++++++++++++++++++++------------------
doc/src/sgml/libpq.sgml | 14 ++++-----
doc/src/sgml/maintenance.sgml | 2 +-
doc/src/sgml/planstats.sgml | 4 +--
doc/src/sgml/ref/create_table.sgml | 6 ++--
doc/src/sgml/storage.sgml | 3 +-
9 files changed, 77 insertions(+), 70 deletions(-)