def clean_indices
      indices = all_indices(unaliased: true)
      indices.each do |index|
        Searchkick::Index.new(index).delete
      end
      indices
    end
def clean_indices
      indices = all_indices(unaliased: true)
      indices.each do |index|
        Searchkick::Index.new(index).delete
      end
      indices
    end
remove old indices that start w/ index_name