@Override
    public int hashCode() {
        return Objects.hash(username, password);
    }
@Test
    void hasAWorkingHashCode() {
        assertThat(credentials.hashCode())
            .hasSameHashCodeAs(new BasicCredentials("u", "p"))
            .isNotEqualTo(new BasicCredentials("u1", "p").hashCode())
            .isNotEqualTo(new BasicCredentials("u", "p1").hashCode());
    }