똑같이 했는데 NSUnknownKeyException 이 뜨는 이유는 뭘까요..?
*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<chattest.UserModel 0x600002a53db0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key profileImageUrl.
