pgsql: Fix a random failure in 038_save_logical_slots_shutdown.pl.

Fix a random failure in 038_save_logical_slots_shutdown.pl.

The test ensures that all the WAL on the publisher is sent to the
subscriber before shutdown by comparing the confirmed_flush_lsn of the
associated slot with the shutdown_checkpoint WAL location. But if the
shutdown_checkpoint location falls into a new page in the WAL then the
check won't work. So, ensure that the shutdown_checkpoint WAL record
doesn't fall into a new page.

Reported-by: Bharath Rupireddy
Author: Bharath Rupireddy
Reviewed-by: Vignesh C, Kuroda Hayato, Amit Kapila
Discussion: https://postgr.es/m/CALj2ACVLzH5CN-h9=S26mdRHPuJ9yDLUw70yh4JOiPw03WL0CQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0b84f5c419a300dc1b1a70cf63b9907208e52643

Modified Files
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src/test/recovery/t/038_save_logical_slots_shutdown.pl | 10 ++++++++++
1 file changed, 10 insertions(+)