Replace mastodon:media:clear and mastodon:feeds:clear rake tasks with (#3180)

sidekiq-scheduler jobs

Resolves #2495

app/workers/scheduler/media_cleanup_scheduler.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+require 'sidekiq-scheduler'
+
+class Scheduler::MediaCleanupScheduler
+  include Sidekiq::Worker
+
+  def perform
+    logger.info 'Cleaning out unattached media attachments'
+    unattached_media.find_each(&:destroy)
+  end
+
+  private
+
+  def unattached_media
+    MediaAttachment.reorder(nil).where(status_id: nil).where('created_at < ?', 1.day.ago)
+  end
+end