Suggested fix from spantaleev

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

group_vars/matrix_servers

@@ -2221,7 +2221,7 @@ matrix_registration_shared_secret: |-
     {
       'synapse': matrix_synapse_registration_shared_secret,
       'dendrite': matrix_dendrite_registration_shared_secret,
-      'conduit': ''
+      'conduit': '',
     }[matrix_homeserver_implementation]
   }}