[pgpool-committers: 5991] pgpool: Fix test failure of extended-query-test/disable-load-balance-al

[Tatsuo Ishii]

Fix test failure of extended-query-test/disable-load-balance-always.

It expected the first SELECT to be sent to load balance node but a
preceding write query (DROP/CREATE TABLE) prevented it because it set
the writing_transaction flag. Fix is, instead of issuing DROP/CREATE
TABLE before the SELECT, issue harmless SET command after the SELECT
in extended query mode.

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=79dbc95377a9071ee79b982514c88a91134d324b

Modified Files
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.../expected/disable-load-balance-always.data      | 17 ++---------------
.../tests/disable-load-balance-always.data         | 22 ++++------------------
2 files changed, 6 insertions(+), 33 deletions(-)