**Build scan:**
https://gradle-enterprise.elastic.co/s/7lj6thapivvd4/tests/:x-pack:plugin:autoscaling:internalClusterTest/org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageIT/testScaleDuringSplitOrClone

**Reproduction line:**
`./gradlew ':x-pack:plugin:autoscaling:internalClusterTest' --tests "org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageIT.testScaleDuringSplitOrClone" -Dtests.seed=E99F6DC356CB8C62 -Dtests.locale=ru-RU -Dtests.timezone=America/Louisville -Druntime.java=17`

**Applicable branches:**
master

**Reproduces locally?:**
No

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageIT&tests.test=testScaleDuringSplitOrClone

**Failure excerpt:**
```
java.lang.NullPointerException: Cannot invoke "org.elasticsearch.xpack.autoscaling.capacity.AutoscalingCapacity.total()" because the return value of "org.elasticsearch.xpack.autoscaling.capacity.AutoscalingDeciderResults.requiredCapacity()" is null

  at __randomizedtesting.SeedInfo.seed([E99F6DC356CB8C62:F8CE624DFC822EC0]:0)
  at org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageIT.testScaleDuringSplitOrClone(ReactiveStorageIT.java:398)
  at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(NativeMethodAccessorImpl.java:-2)
  at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
  at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:568)
  at com.carrotsearch.randomizedtesting.RandomizedRunner.invoke(RandomizedRunner.java:1758)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$8.evaluate(RandomizedRunner.java:946)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$9.evaluate(RandomizedRunner.java:982)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$10.evaluate(RandomizedRunner.java:996)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleSetupTeardownChained$1.evaluate(TestRuleSetupTeardownChained.java:44)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at org.apache.lucene.tests.util.TestRuleThreadAndTestName$1.evaluate(TestRuleThreadAndTestName.java:45)
  at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
  at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:390)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl.forkTimeoutingTask(ThreadLeakControl.java:843)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$3.evaluate(ThreadLeakControl.java:490)
  at com.carrotsearch.randomizedtesting.RandomizedRunner.runSingleTest(RandomizedRunner.java:955)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$5.evaluate(RandomizedRunner.java:840)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$6.evaluate(RandomizedRunner.java:891)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$7.evaluate(RandomizedRunner.java:902)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleStoreClassName$1.evaluate(TestRuleStoreClassName.java:38)
  at com.carrotsearch.randomizedtesting.rules.NoShadowingOrOverridesOnMethodsRule$1.evaluate(NoShadowingOrOverridesOnMethodsRule.java:40)
  at com.carrotsearch.randomizedtesting.rules.NoShadowingOrOverridesOnMethodsRule$1.evaluate(NoShadowingOrOverridesOnMethodsRule.java:40)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleAssertionsRequired$1.evaluate(TestRuleAssertionsRequired.java:53)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
  at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
  at org.apache.lucene.tests.util.TestRuleIgnoreTestSuites$1.evaluate(TestRuleIgnoreTestSuites.java:47)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:390)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl.lambda$forkTimeoutingTask$0(ThreadLeakControl.java:850)
  at java.lang.Thread.run(Thread.java:833)

```
x-pack/plugin/autoscaling/src/internalClusterTest/java/org/elasticsearch/xpack/autoscaling/storage/ReactiveStorageIT.java
final String indexName = randomAlphaOfLength(10).toLowerCase(Locale.ROOT);
        assertAcked(
            prepareCreate(indexName).setSettings(
                Settings.builder()
                    
                    .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, between(0, 5))
                    .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, 6)
                    .put(INDEX_STORE_STATS_REFRESH_INTERVAL_SETTING.getKey(), "0ms")
                    .put(IndexMetadata.INDEX_ROUTING_INCLUDE_GROUP_SETTING.getKey() + "data_tier", "hot")
                    .build()
            ).setWaitForActiveShards(ActiveShardCount.NONE)
        );
        
        updateIndexSettings(indexName, Settings.builder().putNull(DataTier.TIER_PREFERENCE));
        refresh(indexName);
        assertThat(capacity().results().get("warm").requiredCapacity().total().storage().getBytes(), equalTo(0L));
        assertThat(capacity().results().get("cold").requiredCapacity().total().storage().getBytes(), equalTo(0L));
        assertAcked(
            client().admin()
                .indices()
                .updateSettings(
                    new UpdateSettingsRequest(indexName).settings(
                        Settings.builder().put(IndexMetadata.INDEX_ROUTING_INCLUDE_GROUP_SETTING.getKey() + "data_tier", "warm")
                    )
                )
                .actionGet()
        );
        assertThat(capacity().results().get("warm").requiredCapacity().total().storage().getBytes(), Matchers.greaterThan(0L));
        
        assertThat(capacity().results().get("cold").requiredCapacity().total().storage().getBytes(), Matchers.greaterThan(0L));