Update RSpec syntax/usage

Fixes a deprecation warning

app/services/create_account.rb

@@ -49,4 +49,18 @@ class CreateAccount < ApplicationService
   def create_lndhub_wallet(user)
     CreateLndhubWalletJob.perform_later(user)
   end
+
+  def exchange_xmpp_contacts_between_inviter_and_invitee
+    ejabberd = EjabberdApiClient.new
+
+    EjabberdApiClient.add_roster_item({
+      "localuser": @username,
+      "localhost": @domain,
+      "user": @inviter.cn,
+      "host": @inviter.ou,
+      "nick": @username,
+      "group": "Friends",
+      "subs": "both"
+    })
+  end
 end