남은 api

[thdwlsgus0]

• 체크리스트
• /playground/{playgroundApplyId}/cancel (playground 참가취소)
• /playground/{playgroundId} (Playground 수정)
• /playground/{playgroundId}/collaborators (applyCollaborators)
• /playground/{playgroundId}/repo (createPlaygroundGithubRepo)
• /playground/applicants/{playgroundApplyId}/reject (Playground 참가 신청 거절)
• /playground/applicants/{playgroundApplyId}/accept (Playground 참기 신청 수락)