Repair the legacy_hs/pick_tor2web_rendezvous_node unit test

It tried to pick nodes for which only routerinfo_t items are set,
but without setting UseMicroDescriptors to 0.  This won't work any
more, now that we're strict about using the right descriptor types
due to 25691/25692/25213.

src/test/test_hs.c

@@ -361,6 +361,7 @@ test_pick_tor2web_rendezvous_node(void *arg)
 
   /* Parse Tor2webRendezvousPoints as a routerset. */
   options->Tor2webRendezvousPoints = routerset_new();
+  options->UseMicrodescriptors = 0;
   retval = routerset_parse(options->Tor2webRendezvousPoints,
                            tor2web_rendezvous_str,
                            "test_tor2web_rp");