pgsql: Fix collation dependency in test introduced in 8586bf7ed8,take

Fix collation dependency in test introduced in 8586bf7ed8, take 2.

Per buildfarm.  This time I hopefully actually made sure to get all
the cases...

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/863aa55624d891be57b54f8d12e61cb4fa9b70ef

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