matrix: Delegate msisdn

roles/matrix/templates/homeserver.yaml.j2

@@ -1202,7 +1202,7 @@ default_identity_server: https://matrix.org
 #
 account_threepid_delegates:
     #email: https://example.com     # Delegate email sending to example.com
-    #msisdn: http://localhost:8090  # Delegate SMS sending to this local process
+    msisdn: https://vector.im
 
 # Whether users are allowed to change their displayname after it has
 # been initially set. Useful when provisioning users based on the