pgsql: Ensure that STDERR is empty in connect_ok tests

Ensure that STDERR is empty in connect_ok tests

Connections performed via connect_ok() in TAP tests should not write
anything to STDERR.

Author: Jacob Champion <pchampion@vmware.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/9D4FFB61-392B-4A2C-B7E4-911797B4AC14@yesql.se
Discussion: https://postgr.es/m/ec146256e31afa0542f9fa970ec258c5f1a5f98.camel@vmware.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4d373e05286daff05d7fd0f6e4ab7ff4e5304d81

Modified Files
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src/test/perl/PostgreSQL/Test/Cluster.pm | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)