pgsql: doc: Improve some grammar and sentences

doc: Improve some grammar and sentences

90fbf7c has taken care of that for HEAD. This includes the portion of
the fixes that applies to the documentation, where needed depending on
the branch.

Author: Justin Pryzby
Discussion: /messages/by-id/20201227202604.GC26311@telsasoft.com
Backpatch-through: 9.5

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a8c68e7796d4c1d420639b4563a70aee8c7e6f85

Modified Files
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doc/src/sgml/ref/pg_dump.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)