pgsql: Further stabilize output from rolenames regression test.

Further stabilize output from rolenames regression test.

Commit e5209bf37 didn't quite get the job done, as I failed to
notice that chksetconfig() also needed to have its ORDER BY
extended.  Per buildfarm member dory.

Report: https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=dory&dt=2020-09-26%2020%3A10%3A13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3c8819955023694feeaa456ee60853d0d6d0e60a

Modified Files
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src/test/modules/unsafe_tests/expected/rolenames.out | 10 +++++-----
src/test/modules/unsafe_tests/sql/rolenames.sql      |  2 +-
2 files changed, 6 insertions(+), 6 deletions(-)