pgsql: Be more careful about port selection in src/test/ldap/.

Be more careful about port selection in src/test/ldap/.

Don't just assume that the next port is free; it might not be, or
if we're really unlucky it might even be out of the TCP range.
Do it honestly with two get_free_port() calls instead.

This is surely a pretty low-probability problem, but I think it
explains a buildfarm failure seen today, so let's fix it.

Back-patch to v11 where this script was added.

Discussion: https://postgr.es/m/25124.1568052346@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3146f5257f16d34c95163974f42a13d99141b977

Modified Files
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src/test/ldap/t/001_auth.pl | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)