pgsql: Revert "Use WAIT FOR LSN in PostgreSQL::Test::Cluster::wait_for_

Revert "Use WAIT FOR LSN in PostgreSQL::Test::Cluster::wait_for_catchup()"

This reverts commit f30848cb05d4d63e1a5a2d6a9d72604f3b63370d.  Due to
buildfarm failures related to recovery conflicts while executing the
WAIT FOR command.  It appears that WAIT FOR still holds xmin for a while.

Reported-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL0OQR8dQtsNBSaA3FNNyQeFabdeRVzurm0b7Xtp592g%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e54ce0b2da62ac71e3b2a5212f32e82b07bf39a5

Modified Files
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src/test/perl/PostgreSQL/Test/Cluster.pm | 59 +-------------------------------
1 file changed, 1 insertion(+), 58 deletions(-)