**Build scan:**
https://gradle-enterprise.elastic.co/s/2p5qyrcuzi35i/tests/:modules:data-streams:internalClusterTest/org.elasticsearch.datastreams.lifecycle.DataLifecycleServiceIT/testDataLifecycleServiceConfiguresTheMergePolicy

**Reproduction line:**
```
gradlew ':modules:data-streams:internalClusterTest' --tests "org.elasticsearch.datastreams.lifecycle.DataLifecycleServiceIT.testDataLifecycleServiceConfiguresTheMergePolicy" -Dtests.seed=E37829DCD2B52CAC -Dtests.locale=sr-Latn-ME -Dtests.timezone=Australia/Adelaide -Druntime.java=20
```

**Applicable branches:**
main

**Reproduces locally?:**
Didn't try

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.datastreams.lifecycle.DataLifecycleServiceIT&tests.test=testDataLifecycleServiceConfiguresTheMergePolicy

**Failure excerpt:**
```
java.lang.AssertionError: 
Expected: is "5"
     but: was "16"

  at __randomizedtesting.SeedInfo.seed([E37829DCD2B52CAC:78854EF4EC3C97D0]:0)
  at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:18)
  at org.junit.Assert.assertThat(Assert.java:956)
  at org.junit.Assert.assertThat(Assert.java:923)
  at org.elasticsearch.datastreams.lifecycle.DataLifecycleServiceIT.lambda$testDataLifecycleServiceConfiguresTheMergePolicy$16(DataLifecycleServiceIT.java:628)
  at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1172)
  at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1145)
  at org.elasticsearch.datastreams.lifecycle.DataLifecycleServiceIT.testDataLifecycleServiceConfiguresTheMergePolicy(DataLifecycleServiceIT.java:625)
  at jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
  at java.lang.reflect.Method.invoke(Method.java:578)
  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:48)
  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:1623)

```
modules/data-streams/src/internalClusterTest/java/org/elasticsearch/datastreams/lifecycle/DataStreamLifecycleServiceIT.java
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;
import static org.elasticsearch.cluster.metadata.DataStreamTestHelper.backingIndexEqualTo;
import static org.elasticsearch.cluster.metadata.IndexMetadata.APIBlock.READ_ONLY;
import static org.elasticsearch.cluster.metadata.MetadataIndexTemplateService.DEFAULT_TIMESTAMP_FIELD;
import static org.elasticsearch.datastreams.lifecycle.DataStreamLifecycleService.DATA_STREAM_MERGE_POLICY_TARGET_FACTOR_SETTING;
import static org.elasticsearch.datastreams.lifecycle.DataStreamLifecycleService.DATA_STREAM_MERGE_POLICY_TARGET_FLOOR_SEGMENT_SETTING;
import static org.elasticsearch.datastreams.lifecycle.DataStreamLifecycleService.ONE_HUNDRED_MB;
import static org.elasticsearch.datastreams.lifecycle.DataStreamLifecycleService.TARGET_MERGE_FACTOR_VALUE;
import static org.elasticsearch.index.IndexSettings.LIFECYCLE_ORIGINATION_DATE;
import static org.elasticsearch.indices.ShardLimitValidator.SETTING_CLUSTER_MAX_SHARDS_PER_NODE;
import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.notNullValue;
import static org.hamcrest.Matchers.nullValue;
import static org.hamcrest.Matchers.startsWith;
public class DataStreamLifecycleServiceIT extends ESIntegTestCase {
    private static final Logger logger = LogManager.getLogger(DataStreamLifecycleServiceIT.class);
    @Override
    protected Collection<Class<? extends Plugin>> nodePlugins() {
        return List.of(DataStreamsPlugin.class, MockTransportService.TestPlugin.class);
    }
    protected boolean ignoreExternalCluster() {
        return true;