pgsql: Remove TAP test for createdb --lc-ctype

Remove TAP test for createdb --lc-ctype

OpenBSD falls back to "C" when using an incorrect input with setlocale()
and LC_CTYPE, causing this test, introduced by 008cf04, to fail. This
removes the culprit test to avoid the portability issue.

Per report from Robert Haas, via buildfarm member curculio.

Discussion: /messages/by-id/CA+TgmoZ6ddh3mHD9gU8DvNYoFmuJaYYn1+4AvZNp25vTdRwCAQ@mail.gmail.com
Backpatch-through: 11

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/8e076f4f9ae3c19c8142e88ca1b6b1d25899dc64

Modified Files
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src/bin/scripts/t/020_createdb.pl | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)