fix: http response를 200에서 201로 변경 (#12)

Author: can019

src/main/java/com/example/base/domain/user/controller/UserController.java

@@ -2,8 +2,9 @@
 
 import com.example.base.domain.user.domain.User;
 import com.example.base.domain.user.service.UserService;
-import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 
@@ -17,7 +18,8 @@ public UserController(UserService userService){
     }
 
     @GetMapping("/user")
-    public String createUser(){
-        return this.userService.createUser(new User()).toString();
+    public ResponseEntity createUser(){
+        String userId =  this.userService.createUser(new User()).toString();
+        return new ResponseEntity(userId, HttpStatus.CREATED);
     }
 }