fix md syntax

tsa/howto/ganeti.mdwn

@@ -612,7 +612,7 @@ on the size of the cluster (in terms of core memory usage).
 Once the reboot is completed, all instances might end up on a single
 machine, and the cluster might need to be rebalanced, see
 below. (Note: the update script should eventually do that, see [ticket
-#33406](https://trac.torproject.org/projects/tor/ticket/33406)).
+33406](https://trac.torproject.org/projects/tor/ticket/33406)).
 
 ## Rebalancing a cluster