pgsql: pg_regress: Promptly detect failed postmaster startup.

pg_regress: Promptly detect failed postmaster startup.

Detect it the way pg_ctl's wait_for_postmaster() does.  When pg_regress
spawned a postmaster that failed startup, we were detecting that only
with "pg_regress: postmaster did not respond within 60 seconds".
Back-patch to 9.4 (all supported versions).

Reviewed by Tom Lane.

Discussion: https://postgr.es/m/20181231172922.GA199150@gust.leadboat.com

Branch
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REL9_4_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/309d16f073fdbc8b5da6a8a7ff4afad01c78e7f6

Modified Files
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src/test/regress/pg_regress.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)