pgsql: Correct psql documentation example

Correct psql documentation example

An example in the psql documentation had an incorrect field name from
what the command actually produced.

Pointed out by Fabien COELHO

Back-patch to 9.6 where the example was added.

Discussion: https://postgr.es/m/alpine.DEB.2.20.1611291349400.19314@lancre

Branch
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REL9_6_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/40eb468a1b2678475b648617bf5fc428739eb807

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