Refactor consumer factory

spec/factories/consumer.rb

@@ -3,12 +3,15 @@
 FactoryBot.define do
   factory :consumer do
     name { 'openHPI' }
-    oauth_key { SecureRandom.hex }
-    oauth_secret { SecureRandom.hex }
     singleton_consumer
   end
 
   trait :singleton_consumer do
-    initialize_with { Consumer.where(name: name).first_or_create }
+    initialize_with do
+      Consumer.find_or_initialize_by(name: name) do |consumer|
+        consumer.oauth_key = SecureRandom.hex
+        consumer.oauth_secret = SecureRandom.hex
+      end
+    end
   end
 end