@Test
    void testPluralSuffix_3b() {
        assertThat(pluralSuffix(List.of(1)))
                .isEqualTo("");
        assertThat(pluralSuffix(List.of(1, 2)))
                .isEqualTo("s");
    }
Make sure the two functions are reversible
stroom-util-shared/src/test/java/stroom/util/shared/TestStringUtil.java