appliance/postgresql: Don’t reuse TCP ports in tests
appliance/postgresql: Don’t reuse TCP ports in tests

Reusing ports is flaky, as the kernel can keep them in use even after
the process that was utilizing them exits.

Signed-off-by: Jonathan Rudenberg <3692bfa45759a67d83aedf0045f6cb635a966abf@titanous.com>

philiplb/flynn,flynn/flynn,benbjohnson/flynn,philiplb/flynn,flynn/flynn,flynn/flynn,lmars/flynn,lmars/flynn,benbjohnson/flynn,philiplb/flynn,flynn/flynn,philiplb/flynn,benbjohnson/flynn,philiplb/flynn,flynn/flynn,lmars/flynn,benbjohnson/flynn,benbjohnson/flynn,benbjohnson/flynn,lmars/flynn,lmars/flynn