pgsql: Force nodes for SSL tests to start in TCP mode

Force nodes for SSL tests to start in TCP mode

Currently they are started in unix socket mode in ost cases, and then
converted to run in TCP mode. This can result in port collisions, and
there is no virtue in startng in unix socket mode, so start as we will
be going on.

Discussion: https://postgr.es/m/d6ee8761-39d1-0033-1afb-d5a57ee056f2@gmail.com

Backpatch to all live branches (12 and up).

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/94c2386878f01404ec9f4a7d5bcbbb21bee6b550

Modified Files
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src/test/ssl/t/SSLServer.pm | 6 ++++++
1 file changed, 6 insertions(+)