pgsql: Use shorter file names in the upgrade logical slots test.

Use shorter file names in the upgrade logical slots test.

The longer file names exceeded the Windows path limit on buildfarm animal
fairywren.

Diagnosed-by: Hou Zhijie
Author: Hayato Kuroda
Reviewed-by: Bharath Rupireddy
Discussion: http://postgr.es/m/OS0PR01MB57160DF709ACD02248DB830C94DDA@OS0PR01MB5716.jpnprd01.prod.outlook.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b195e6d482b8424827c7371bf34b48dacc37994e

Modified Files
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src/bin/pg_upgrade/check.c                         |  2 +-
...l_replication_slots.pl => 003_logical_slots.pl} | 86 +++++++++++-----------
2 files changed, 44 insertions(+), 44 deletions(-)