pgsql: Tighten test in contrib/bloom/t/001_wal.pl.

Tighten test in contrib/bloom/t/001_wal.pl.

Make bloom WAL test compare psql output text, not just result codes;
this was evidently the intent all along, but it was mis-coded.
In passing, make sure we will notice any failure in setup steps.

Alexander Korotkov, reviewed by Michael Paquier and Masahiko Sawada

Discussion: https://postgr.es/m/CAPpHfdtohPdQ9rc5mdWjxq+3VsBNw534KV_5O65dTQrSdVJNgw@mail.gmail.com

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/859662c26cf9eac8bfa50a83913523606bdf3e28

Modified Files
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contrib/bloom/t/001_wal.pl | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)