test: remove hidden use of common.PORT in parallel tests
common.hasMultiLocalhost() uses common.PORT under the hood. This is problematic in parallel tests because another test using port 0 to get an arbitrary open port may end up getting common.PORT before the test using common.PORT gets it.
Therefore, change common.PORT to port 0 in common.hasMultiLocalhost().
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
commit message follows commit guidelines
Affected core subsystem(s)
test