BUG : 작가 팔로우 취소하기 artistId -> accountId로 수정

Author: taeyoung0524

src/user/service/user.service.js

@@ -297,7 +297,7 @@ export const UserService = {
 
     // 작가 팔로우 취소하기 
     async CancelArtistFollow(accountId, artistId) {
-        const artist = await UserRepository.findArtistById(artistId);
+        const artist = await UserRepository.findArtistById(accountId);
 
         if(!artist)
             throw new ArtistNotFound();