pgsql: Avoid context dependency in test case added by 9a71989a8.

Avoid context dependency in test case added by 9a71989a8.

It's not quite clear to me why this didn't show up in my local
check-world testing, but some of the buildfarm evidently runs
this test with a different database name. Adjust the test
so that that doesn't affect the reported error messages.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/88824e68611a88a4ef7218c093810a94f86e12e0

Modified Files
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src/test/modules/unsafe_tests/expected/setconfig.out | 8 ++++----
src/test/modules/unsafe_tests/sql/setconfig.sql | 4 ++++
2 files changed, 8 insertions(+), 4 deletions(-)