pgsql: Fix random regression failure in test case "collate.icu.utf8"

Fix random regression failure in test case "collate.icu.utf8"

This is a fix similar to 2d7d67cc, where slight plan alteration can
cause a random failure of this regression test because of an incorect
tuple ordering, except that this one involves lookups of pg_type.
Similarly to the other case, add ORDER BY clauses to ensure the output
order.

The failure has been seen at least once on buildfarm member skink.

Reported-by: Thomas Munro
Discussion: https://postgr.es/m/CA+hUKGLjR9ZBvhXcr9b-NSBHPw9aRgbjyzGE+kqLsT4vwX+nkQ@mail.gmail.com
Backpatch-through: 12

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/b626483bd97be374ad827f800171478773ad8282

Modified Files
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src/test/regress/expected/collate.icu.utf8.out | 6 ++++--
src/test/regress/sql/collate.icu.utf8.sql | 6 ++++--
2 files changed, 8 insertions(+), 4 deletions(-)