### CI Link

https://gradle-enterprise.elastic.co/s/pzjicoqh7nuhq

### Repro line

./gradlew ':server:internalClusterTest' --tests "org.elasticsearch.snapshots.BlobStoreIncrementalityIT.testRecordCorrectSegmentCountsWithBackgroundMerges" -Dtests.seed=DEA1040A4A18200C -Dtests.locale=ar-KW -Dtests.timezone=Etc/Universal -Druntime.java=17

### Does it reproduce?

Yes

### Applicable branches

main, 8.4

### Failure history

First time it fails in the last 7 days: https://gradle-enterprise.elastic.co/scans/tests?search.timeZoneId=Europe/Bucharest&tests.container=org.elasticsearch.snapshots.BlobStoreIncrementalityIT&tests.test=testRecordCorrectSegmentCountsWithBackgroundMerges

### Failure excerpt

```
org.elasticsearch.snapshots.BlobStoreIncrementalityIT > testRecordCorrectSegmentCountsWithBackgroundMerges FAILED
    java.lang.AssertionError: 
    Expected: a value less than <3L>
         but: <3L> was equal to <3L>
        at __randomizedtesting.SeedInfo.seed([DEA1040A4A18200C:C81912C0892C8B7B]: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.snapshots.BlobStoreIncrementalityIT.lambda$testRecordCorrectSegmentCountsWithBackgroundMerges$0(BlobStoreIncrementalityIT.java:236)
        at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1104)
        at org.elasticsearch.snapshots.BlobStoreIncrementalityIT.testRecordCorrectSegmentCountsWithBackgroundMerges(BlobStoreIncrementalityIT.java:234)
```
server/src/internalClusterTest/java/org/elasticsearch/snapshots/BlobStoreIncrementalityIT.java
/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the Elastic License
 * 2.0 and the Server Side Public License, v 1; you may not use this file except
 * in compliance with, at your election, the Elastic License 2.0 or the Server
 * Side Public License, v 1.
 */
package org.elasticsearch.snapshots;
import org.elasticsearch.action.DocWriteResponse;
import org.elasticsearch.action.admin.cluster.snapshots.restore.RestoreSnapshotResponse;
import org.elasticsearch.action.admin.cluster.snapshots.status.SnapshotStats;
import org.elasticsearch.action.admin.cluster.snapshots.status.SnapshotStatus;
import org.elasticsearch.action.admin.indices.forcemerge.ForceMergeResponse;