public void update(final String comment, final Long writerId) {
        validateWriterId(writerId);
        this.content = comment;
    }
@Test
    void 댓글을_업데이트한다() {
        // given
        Comment comment = 댓글_생성();
        String edit = "edit";

        // when
        comment.update(edit, comment.getWriterId());

        // then
        assertThat(comment.getContent()).isEqualTo(edit);
    }