pgsql: Detect format-string mistakes in the libpq_pipeline test module.

Detect format-string mistakes in the libpq_pipeline test module.

I happened to notice that libpq_pipeline's private implementation
of pg_fatal lacked any pg_attribute_printf decoration. Indeed,
adding that turned up a mistake! We'd likely never have noticed
because the error exits in this code are unlikely to get hit,
but still, it's a bug.

We're so used to having the compiler check this stuff for us that
a printf-like function without pg_attribute_printf is a land mine.
I wonder if there is a way to detect such omissions.

Back-patch to v14 where this code came in.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cf2c7a736e4939ff0d6cf2acd29b17eea3bca7c2

Modified Files
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src/test/modules/libpq_pipeline/libpq_pipeline.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)