pgsql: ci: freebsd: Specify debug_parallel_query=regress

ci: freebsd: Specify debug_parallel_query=regress

A lot of buildfarm animals run with debug_parallel_query=regress, while CI
didn't test that. That lead to the annoying situation of only noticing related
test instabilities after merging changes upstream.

FreeBSD was chosen because it's a relatively fast task. It also tests
debug_write_read_parse_plan_trees etc, which probably is exercised a bit more
heavily with debug_parallel_query=regress.

Discussion: /messages/by-id/zbuk4mlov22yfoktf5ub3lwjw2b7ezwphwolbplthepda42int@h6wpvq7orc44

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0a2f5df88168e3d8c50e3a26bf1ca45c61f9d6f2

Modified Files
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.cirrus.tasks.yml | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)