♻️ refactor: Observer 패턴을 적용하여 회원 탈퇴 로직 개선#258

leeseojun34 merged 1 commit intoprgrms-web-devcourse-final-project:mainprgrms-web-devcourse-final-project/WEB5_6_DOD_BE:mainfrom

leeseojun34:lsj/refactor/withdrawleeseojun34/Ittaeok-BE-server:lsj/refactor/withdrawCopy head branch name to clipboard