pgsql: Probe only 127.0.0.1 when looking for ports on Unix.

Probe only 127.0.0.1 when looking for ports on Unix.

Commit c0985099, later adjusted by commit 4ab02e81, probed 0.0.0.0
in addition to 127.0.0.1, for the benefit of Windows build farm
animals.  It isn't really useful on Unix systems, and turned out to
be a bit inconvenient to users of some corporate firewall software.
Switch back to probing just 127.0.0.1 on non-Windows systems.

Back-patch to 9.6, like the earlier changes.

Discussion: https://postgr.es/m/CA%2BhUKG%2B21EPwfgs4m%2BtqyRtbVqkOUvP8QQ8sWk9%2Bh55Aub1H3A%40mail.gmail.com

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/1f3bcb4972009c8af7b71d1526559475a248f77a

Modified Files
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src/test/perl/PostgresNode.pm | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)