Subscription API

POST /api/subscription HTTP/1.1
Content-Type: application/json;charset=UTF-8
Content-Length: 130
Host: localhost:8080

{
  "groupId" : 1,
  "message" : "그룹에 가입하고 싶어요. 홍대 라멘집과 돈까스집은 모두 가봤습니다."
}

{
  "success" : true,
  "result" : {
    "subscriptionId" : 1
  }
}

PATCH /api/subscription/1/status HTTP/1.1
Content-Type: application/json;charset=UTF-8
Content-Length: 25
Host: localhost:8080

{
  "status" : "ACCEPT"
}

{
  "success" : true,
  "result" : true
}

GET /api/subscription/users?groupId=1 HTTP/1.1
Content-Type: application/json;charset=UTF-8
Host: localhost:8080

{
  "success" : true,
  "result" : [ {
    "subscriptionId" : 1,
    "applicantId" : "43f28ebf-8921-477c-8089-dfa50d587697",
    "applicantNickname" : "유저1",
    "message" : "그룹에 가입하고 싶어요. 홍대 라멘집과 돈까스집은 모두 가봤습니다.",
    "createdAt" : "2023-07-09T22:15:18.176497"
  }, {
    "subscriptionId" : 2,
    "applicantId" : "1ee2aee3-1410-4f00-8a4e-447459bf7c90",
    "applicantNickname" : "유저2",
    "message" : "아들아 엄마다",
    "createdAt" : "2023-07-09T22:15:18.176517"
  } ]
}