L1007E: Property or field 'name' cannot be found on null 에러

보통 tymeleaf에서 th:if할 때 값을 `${}`로 표시 안해서
```html
<h1>Score Result</h1>
<div th:if="${dto}">
  <p th:text="${dto.name}"></p>
  <p th:text="${dto.kor}"></p>
  <p th:text="${dto.eng}"></p>
  <p th:text="${dto.math}"></p>
  <p th:text="${sum}"></p>
  <p th:text="${avg}"></p>
</div>
```