pgsql: Revert test case added by commit 1e165d05fe06a9072867607886f818b

Revert test case added by commit 1e165d05fe06a9072867607886f818bc255507db.

The buildfarm is still showing at least three distinct behaviors for
a bad locale name in CREATE COLLATION. Although this test was helpful
for getting the error reporting code into some usable shape, it doesn't
seem worth carrying multiple expected-files in order to support the
test in perpetuity. So pull it back out.

Discussion: https://postgr.es/m/CAKKotZS-wcDcofXDCH=sidiuajE+nqHn2CGjLLX78anyDmi3gQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/32ca22b02da9d8088b58b3dc64ad78464c7513a3

Modified Files
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src/test/regress/expected/collate.out | 3 ---
src/test/regress/sql/collate.sql | 1 -
2 files changed, 4 deletions(-)