As the title says. These tasks should be batched because they can arise from ILM actions.

Relates #77466
server/src/test/java/org/elasticsearch/cluster/metadata/MetadataIndexAliasesServiceTests.java
applyHiddenAliasMix(before, null, null);
            applyHiddenAliasMix(before, false, false);
            applyHiddenAliasMix(before, false, null);
            applyHiddenAliasMix(before, null, false);
            applyHiddenAliasMix(before, true, true);
        }
        {
            Exception exception = expectThrows(
                IllegalStateException.class,
                () -> applyHiddenAliasMix(before, true, randomFrom(false, null))
            );
            assertThat(exception.getMessage(), startsWith("alias [alias] has is_hidden set to true on indices ["));
        }
        {
            Exception exception = expectThrows(
                IllegalStateException.class,
                () -> applyHiddenAliasMix(before, randomFrom(false, null), true)
            );
            assertThat(exception.getMessage(), startsWith("alias [alias] has is_hidden set to true on indices ["));
        }
    }
    public void testAliasesForDataStreamBackingIndicesNotSupported() {
        long epochMillis = randomLongBetween(1580536800000L, 1583042400000L);
        String dataStreamName = "foo-stream";
        String backingIndexName = DataStream.getDefaultBackingIndexName(dataStreamName, 1, epochMillis);
        IndexMetadata indexMetadata = IndexMetadata.builder(backingIndexName)
            .settings(settings(Version.CURRENT))
            .numberOfShards(1)
            .numberOfReplicas(1)
            .build();