net: Increase run frequency for dedicated server.

This should really be changed to block until new packets are
received, but until then, this is at least an improvement. 10ms is
too coarsely-grained considering how critical the latency is to the
game.

src/net_dedicated.c

@@ -73,7 +73,8 @@ void NET_DedicatedServer(void)
     while (true)
     {
         NET_SV_Run();
-        I_Sleep(10);
+        // TODO: Block on socket instead of polling.
+        I_Sleep(1);
     }
 }