pgsql: Fix pg_upgrade's cross-version tests when old < 18

Fix pg_upgrade's cross-version tests when old < 18

Because in the 18 cycle we turned checksums on by default with commit
04bec894a04c, and pg_upgrade fails if the setting doesn't match in old
and new clusters, the built-in cross-version pg_upgrade test is failing
if the old version is older than 18. Fix the script so that it creates
the old cluster with checksums enabled (-k) in cross-version scenarios.

This went unnoticed because the buildfarm doesn't use the same test code
for cross-version testing.

Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Discussion: https://postgr.es/m/202411071838.7fgkb7uvavvz@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/38c18710b37a2d0e343a8d6b6333cff31498459b

Modified Files
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src/bin/pg_upgrade/t/002_pg_upgrade.pl | 4 ++++
1 file changed, 4 insertions(+)