pgsql: Consider a failed process as a failed test in pg_regress

Consider a failed process as a failed test in pg_regress

Commit 55de145d1cf added reporting of child process failures, but the
test suite is still allowed to pass even if the process failed. Since
regress tests are higher level tests, a false positive is more likely
in this case so report failed test processes as failed tests.

Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/82C46B5E-1821-4039-82C2-56BCA5992989@yesql.se
Discussion: https://postgr.es/m/20221122235636.4frx7hjterq6bmls@awork3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/337903a16fb0980950a98a17c388b28da8642446

Modified Files
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src/test/regress/pg_regress.c | 37 +++++++++++++++++++++++++------------
1 file changed, 25 insertions(+), 12 deletions(-)