Compatibility with new eslint config spec

Eslint announced a new config spec. https://eslint.org/docs/latest/user-guide/configuring/configuration-files-new <img width="879" alt="스크린샷 2022-09-09 오후 10 07 49" src="https://user-images.githubusercontent.com/28584151/189357000-2016d6e8-d655-4299-9bcd-b062c0cedb7f.png"> According to [eslint's official blog](https://eslint.org/blog/2022/08/new-config-system-part-2/), though backwa.