**Build scan:**
https://gradle-enterprise.elastic.co/s/gw4irn72s42ok/tests/:x-pack:plugin:autoscaling:test/org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageDeciderDecisionTests/testStoragePreventsMove

**Reproduction line:**
```
gradlew ':x-pack:plugin:autoscaling:test' --tests "org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageDeciderDecisionTests.testStoragePreventsMove" -Dtests.seed=C63160D29048E869 -Dtests.locale=zh-HK -Dtests.timezone=Africa/Tunis -Druntime.java=19
```

**Applicable branches:**
main

**Reproduces locally?:**
Yes

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

**Failure excerpt:**
```
java.lang.AssertionError: 
Expected: <ShardsSize[sizeInBytes=3, shardIds=[[test-7][0], [test-7][1]]]>
     but: was <ShardsSize[sizeInBytes=2, shardIds=[[test-7][0], [test-7][1]]]>

  at __randomizedtesting.SeedInfo.seed([C63160D29048E869:C67D527F55E78200]: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.xpack.autoscaling.storage.ReactiveStorageDeciderDecisionTests.verify(ReactiveStorageDeciderDecisionTests.java:415)
  at org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageDeciderDecisionTests.verify(ReactiveStorageDeciderDecisionTests.java:399)
  at org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageDeciderDecisionTests.verify(ReactiveStorageDeciderDecisionTests.java:395)
  at org.elasticsearch.xpack.autoscaling.storage.ReactiveStorageDeciderDecisionTests.testStoragePreventsMove(ReactiveStorageDeciderDecisionTests.java:246)
  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)

```
x-pack/plugin/autoscaling/src/test/java/org/elasticsearch/xpack/autoscaling/storage/ReactiveStorageDeciderDecisionTests.java
private Set<ShardId> subjectShards;
    
    private final AllocationDecider mockCanAllocateDiskDecider = new AllocationDecider() {
        @Override
        public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
            if (subjectShards.contains(shardRouting.shardId()) && node.node().getName().startsWith("hot")) {
                return allocation.decision(Decision.NO, DiskThresholdDecider.NAME, "test");
            }
            return super.canAllocate(shardRouting, node, allocation);
        }
    };
    
    private final AllocationDecider mockCanRemainDiskDecider = new AllocationDecider() {
        @Override
        public Decision canRemain(IndexMetadata indexMetadata, ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
            if (subjectShards.contains(shardRouting.shardId()) && node.node().getName().startsWith("hot")) return allocation.decision(
                Decision.NO,
                DiskThresholdDecider.NAME,
                "test"
            );
            return super.canRemain(indexMetadata, shardRouting, node, allocation);
        }
    };
    @Before
    public void setup() {
        ClusterState clusterState = ClusterState.builder(new ClusterName("test")).build();
        clusterState = addRandomIndices(hotNodes, hotNodes, clusterState);
        clusterState = addDataNodes(DATA_HOT_NODE_ROLE, "hot", clusterState, hotNodes);
        clusterState = addDataNodes(DATA_WARM_NODE_ROLE, "warm", clusterState, warmNodes);