pgsql: Tweak duplicate-index-column regression test to avoid locale sen

Tweak duplicate-index-column regression test to avoid locale sensitivity.

The originally-chosen test case gives different results in es_EC locale
because of unusual rule for sorting strings beginning with "LL".  Adjust
the comparison value to avoid that, while hopefully not introducing new
locale dependencies elsewhere.  Per report from Jaime Casanova.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/de5a08c59de39df07599723cb212ae8297903f48

Modified Files
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src/test/regress/expected/create_index.out |    8 ++++----
src/test/regress/sql/create_index.sql      |    4 ++--
2 files changed, 6 insertions(+), 6 deletions(-)