Add task in order to delete unconfirmed users (older than 2days) (#1571)

* add task in order to delete unconfirmed user

* change 7 days to 2

lib/tasks/mastodon.rake

@@ -75,6 +75,13 @@ namespace :mastodon do
     end
   end
 
+  namespace :users do
+    desc 'clear unconfirmed users'
+    task clear: :environment do
+      User.where('confirmed_at is NULL AND confirmation_sent_at <= ?', 2.days.ago).find_each(&:destroy)
+    end
+  end
+
   namespace :maintenance do
     desc 'Update counter caches'
     task update_counter_caches: :environment do