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_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e06713ab6eaca9e74f405de1195a9c020f886dd9

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