pgsql: Fix test instability

Fix test instability

On FreeBSD, the new test fails due to a WAL file being removed before
the standby has had the chance to copy it.  Fix by adding a replication
slot to prevent the removal until after the standby has connected.

Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reported-by: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAEze2Wj5nau_qpjbwihvmXLfkAWOZ5TKdbnqOc6nKSiRJEoPyQ@mail.gmail.com

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/4d8d85740c0228b04a10818587b70f4ae3a2beba

Modified Files
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src/test/recovery/t/033_replay_tsp_drops.pl | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)