[pgpool-committers: 8694] pgpool: Allow to run pgpool_setup on PostgreSQL 15.

[Tatsuo Ishii]

Allow to run pgpool_setup on PostgreSQL 15.

basebackup.sh created by pgpool_setup uses pg_start_backup() and
pg_stop_backup().  PostgreSQL 15 renamed them. But there's more
problem. The renamed functions (pg_backup_start() and
pg_backup_stop()) must be called within a same connection. Adapting
these requires non-trivial changes. So I decided to rewrite the code
to not use pg_start_backup() and pg_stop_backup() so that it uses
pg_basebackup command instead.

Per https://www.pgpool.net/mantisbt/view.php?id=757

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=1ccdfc036e0b1299cd5ccea9be7714bbdbfa2d5f

Modified Files
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src/test/pgpool_setup.in | 43 +++++++++++++++----------------------------
1 file changed, 15 insertions(+), 28 deletions(-)