Add retention policy for cached content and media (#19232)

app/lib/vacuum/backups_vacuum.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+class Vacuum::BackupsVacuum
+  def initialize(retention_period)
+    @retention_period = retention_period
+  end
+
+  def perform
+    vacuum_expired_backups! if retention_period?
+  end
+
+  private
+
+  def vacuum_expired_backups!
+    backups_past_retention_period.in_batches.destroy_all
+  end
+
+  def backups_past_retention_period
+    Backup.unscoped.where(Backup.arel_table[:created_at].lt(@retention_period.ago))
+  end
+
+  def retention_period?
+    @retention_period.present?
+  end
+end