**Build scan:**
https://gradle-enterprise.elastic.co/s/p5lp5uc42gpcu/tests/:modules:data-streams:internalClusterTest/org.elasticsearch.datastreams.DataStreamIT/testGetDataStream

**Reproduction line:**
```
./gradlew ':modules:data-streams:internalClusterTest' --tests "org.elasticsearch.datastreams.DataStreamIT.testGetDataStream" -Dtests.seed=2E01668E169440D7 -Dbuild.snapshot=false -Dtests.jvm.argline="-Dbuild.snapshot=false" -Dtests.locale=de-CH -Dtests.timezone=America/North_Dakota/Center -Druntime.java=19
```

**Applicable branches:**
main

**Reproduces locally?:**
Yes

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

**Failure excerpt:**
```
java.lang.AssertionError: 
Expected: is <{
  "data_retention" : "146448103625734ms"
}>
     but: was null

  at __randomizedtesting.SeedInfo.seed([2E01668E169440D7:E1F01CC50A5BA920]: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.DataStreamIT.testGetDataStream(DataStreamIT.java:1304)
  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:1589)

```
modules/data-streams/src/internalClusterTest/java/org/elasticsearch/datastreams/DataStreamIT.java
e.getMessage(),
            equalTo(
                "The provided expressions ["
                    + backingIndex
                    + "] match a backing index belonging to data stream ["
                    + dataStreamName
                    + "]. Data stream backing indices don't "
                    + "support aliases."
            )
        );
    }
    public void testAddDataStreamAliasesMixedExpressionValidation() throws Exception {
        createIndex("metrics-myindex");
        putComposableIndexTemplate("id1", List.of("metrics-*"));
        String dataStreamName = "metrics-foo";
        CreateDataStreamAction.Request createDataStreamRequest = new CreateDataStreamAction.Request(dataStreamName);
        client().execute(CreateDataStreamAction.INSTANCE, createDataStreamRequest).get();
        AliasActions addAction = new AliasActions(AliasActions.Type.ADD).index("metrics-*").aliases("my-alias");
        IndicesAliasesRequest aliasesAddRequest = new IndicesAliasesRequest();
        aliasesAddRequest.addAliasAction(addAction);
        Exception e = expectThrows(IllegalArgumentException.class, () -> client().admin().indices().aliases(aliasesAddRequest).actionGet());
        assertThat(e.getMessage(), equalTo("expressions [metrics-*] that match with both data streams and regular indices are disallowed"));
    }
    public void testRemoveDataStreamAliasesMixedExpression() throws Exception {
        createIndex("metrics-myindex");
        putComposableIndexTemplate("id1", List.of("metrics-*"));
        String dataStreamName = "metrics-foo";
        CreateDataStreamAction.Request createDataStreamRequest = new CreateDataStreamAction.Request(dataStreamName);
        client().execute(CreateDataStreamAction.INSTANCE, createDataStreamRequest).get();
        IndicesAliasesRequest aliasesAddRequest = new IndicesAliasesRequest();