Fix: close intro circuit if no more intro points are usable

Once a NACK is received on the intro circuit, tor tries an other usable one
by extending the current circuit to it. If no more intro points are usable,
now close the circuit.

Fixes #14224

Signed-off-by: David Goulet <dgoulet@ev0ke.net>

src/or/rendclient.c

@@ -468,6 +468,10 @@ rend_client_introduction_acked(origin_circuit_t *circ,
       /* XXXX If that call failed, should we close the rend circuit,
        * too? */
       return result;
+    } else {
+      /* Close circuit because no more intro points are usable thus this
+       * circuit is not useful anymore. */
+      circuit_mark_for_close(TO_CIRCUIT(circ), END_CIRC_REASON_FINISHED);
     }
   }
   return 0;