The tests intermittently crash on 2008 with RPC_S_SERVER_TOO_BUSY.  I suspect
this is due to the server spawned in run_server having a call limit of 20 but
being expected to service 32 threads.  Use the default parameter in an attempt
to prevent this failure.
Signed-off-by: Zebediah Figura <z.figura12@gmail.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>