Update lib/itamae/backend.rb
Update lib/itamae/backend.rb

Co-Authored-By: Yusuke Nakamura <e72707c0d37616a38a63769cf05c930602729971@users.noreply.github.com>
sue445/itamae,itamae-kitchen/itamae,sue445/itamae,itamae-kitchen/itamae