pgsql: Doc: improve example for intarray's uniq() function.

Doc: improve example for intarray's uniq() function.

The previous entry invited confusion between what uniq() does
by itself and what it does when combined with sort().  The latter
usage is pretty useful so we should show it, but add an additional
example to clarify the results of uniq() alone.

Per suggestion from Martin Kalcher.  Back-patch to v13, where
we switched to formatting that supports multiple examples.

Discussion: https://postgr.es/m/165407884456.573551.8779012279828726162@wrigleys.postgresql.org

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c1ad8047a2c22f841e4e3df39696febeb7167e6c

Modified Files
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doc/src/sgml/intarray.sgml | 5 +++++
1 file changed, 5 insertions(+)