Обсуждение: pgsql: Fix some grammar and typos in comments and docs

Fix some grammar and typos in comments and docs

The documentation fixes are backpatched down to where they apply.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20201031020801.GD3080@telsasoft.com
Backpatch-through: 9.6

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/bebad33420044240297e7288d4f311095bab76b9

Modified Files
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doc/src/sgml/auto-explain.sgml  | 2 +-
doc/src/sgml/ddl.sgml           | 2 +-
doc/src/sgml/ref/pg_rewind.sgml | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)