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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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d46eb10c06f411fc370e8255c03ec01c8e49c5f2

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