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_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/b25c106df71fc317e65814e4f301afa05b7b2304

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