public void validatePassword(final String password) {
        if (!this.password.equals(password)) {
            throw new PasswordNotMatchedException();
        }
    }
@Test
    void 패스워드가_다른_경우에_예외를_발생한다() {
        // given
        Member member = 일반_유저_생성();
        String givenPassword = "wrongPassword";

        // when & then
        assertThatThrownBy(() -> member.validatePassword(givenPassword))
                .isInstanceOf(PasswordNotMatchedException.class);
    }