public static FailureBatch indexingFailureBatch(List<IndexingFailure> indexingFailures) {
        return new FailureBatch(indexingFailures, IndexingFailure.class);
    }
@Test
    public void indexingFailureBatch_creationFailsUponMixedTypesOfFailures() {
        assertThatCode(() ->
                FailureBatch.indexingFailureBatch(List.of(createIndexingFailure(), createIndexingFailure(), new CustomIndexingFailure())))
                .isExactlyInstanceOf(IllegalArgumentException.class);
    }