def deduplicate_domain_allows!
      remove_index_if_exists!(:domain_allows, 'index_domain_allows_on_domain')

      @prompt.say 'Deduplicating domain_allows…'
      ActiveRecord::Base.connection.select_all("SELECT string_agg(id::text, ',') AS ids FROM domain_allows GROUP BY domain HAVING count(*) > 1").each do |row|