pgsql: Add diagnostic output on error in pump_until

Add diagnostic output on error in pump_until

When pump_until was moved to Utils.pm in commit 6da65a3f9 the diag
calls were removed, this puts them back.

Per request from Andres Freund.

Discussion: https://postgr.es/m/20220329225819.ahk5u2tax3ez6d2t@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2beb4acff1e83fef6766a5a7d5bbd952444a0b36

Modified Files
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src/test/perl/PostgreSQL/Test/Utils.pm | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)