pgsql: Tweak regression test of pg_walinspect to be less collation-sens

Tweak regression test of pg_walinspect to be less collation-sensitive

\dx was used on pg_walinspect to list its objects in 1.0 but the names
of the objects in this version do not have an order that is always
guaranteed depending on the collation used. Rather than append a
COLLATE clause in the query of \dx, this tweaks the regression test to
produce an output whose order is guaranteed.

Reported-by: Andres Freund
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/20230314215440.gma7g4keswdnldj5@awork3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e643a315fc58deae20877e2e69358c95087fa09a

Modified Files
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contrib/pg_walinspect/expected/oldextversions.out | 12 ++++++++----
contrib/pg_walinspect/sql/oldextversions.sql | 9 +++++++--
2 files changed, 15 insertions(+), 6 deletions(-)