Обсуждение: pgsql: doc: Fix some grammar

doc: Fix some grammar

This is an extraction of the user-visible changes done in 410aa24,
including all the relevant documentation parts.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20220124030001.GQ23027@telsasoft.com
Backpatch-through: 10

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/fcc434047d09428d48341c6faeb29e9bd9d95a4e

Modified Files
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doc/src/sgml/config.sgml            | 4 ++--
doc/src/sgml/ddl.sgml               | 4 ++--
doc/src/sgml/perform.sgml           | 2 +-
doc/src/sgml/protocol.sgml          | 2 +-
doc/src/sgml/ref/pg_receivewal.sgml | 7 +++----
doc/src/sgml/ref/select_into.sgml   | 2 +-
6 files changed, 10 insertions(+), 11 deletions(-)