**Build scan:**
https://gradle-enterprise.elastic.co/s/whiwuz23mtmvq/tests/:x-pack:plugin:rollup:test/org.elasticsearch.xpack.rollup.v2.RollupActionSingleNodeTests/testCannotRollupToExistingIndex

**Reproduction line:**
`./gradlew ':x-pack:plugin:rollup:test' --tests "org.elasticsearch.xpack.rollup.v2.RollupActionSingleNodeTests.testCannotRollupToExistingIndex" -Dtests.seed=9814B01249EAC77D -Dtests.locale=en-SG -Dtests.timezone=Africa/Windhoek -Druntime.java=17`

**Applicable branches:**
main

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

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.xpack.rollup.v2.RollupActionSingleNodeTests&tests.test=testCannotRollupToExistingIndex

**Failure excerpt:**
```
org.elasticsearch.index.IndexNotFoundException: no such index [rollup-testcannotrollupwhileotherrollupinprogress-svlo]

  at __randomizedtesting.SeedInfo.seed([9814B01249EAC77D:325B86553CE92325]:0)
  at org.elasticsearch.cluster.metadata.Metadata.getIndexSafe(Metadata.java:919)
  at org.elasticsearch.cluster.metadata.MetadataDeleteIndexService.deleteIndices(MetadataDeleteIndexService.java:89)
  at org.elasticsearch.cluster.metadata.MetadataDeleteIndexService$1.execute(MetadataDeleteIndexService.java:70)
  at org.elasticsearch.cluster.service.MasterService$UnbatchedExecutor.execute(MasterService.java:515)
  at org.elasticsearch.cluster.service.MasterService.innerExecuteTasks(MasterService.java:959)
  at org.elasticsearch.cluster.service.MasterService.executeTasks(MasterService.java:929)
  at org.elasticsearch.cluster.service.MasterService.runTasks(MasterService.java:261)
  at org.elasticsearch.cluster.service.MasterService$Batcher.run(MasterService.java:165)
  at org.elasticsearch.cluster.service.TaskBatcher.runIfNotProcessed(TaskBatcher.java:110)
  at org.elasticsearch.cluster.service.TaskBatcher$BatchedTask.run(TaskBatcher.java:148)
  at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingRunnable.run(ThreadContext.java:710)
  at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.runAndClean(PrioritizedEsThreadPoolExecutor.java:257)
  at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.run(PrioritizedEsThreadPoolExecutor.java:223)
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
  at java.lang.Thread.run(Thread.java:833)

```
x-pack/plugin/rollup/src/test/java/org/elasticsearch/xpack/rollup/v2/RollupActionSingleNodeTests.java
assertEquals(
                originalDateHistogramBuckets.stream().map(InternalDateHistogram.Bucket::getKeyAsString).collect(Collectors.toList()),
                rollupDateHistogramBuckets.stream().map(InternalDateHistogram.Bucket::getKeyAsString).collect(Collectors.toList())
            );
            for (int i = 0; i < originalDateHistogramBuckets.size(); ++i) {
                InternalDateHistogram.Bucket originalDateHistogramBucket = originalDateHistogramBuckets.get(i);
                InternalDateHistogram.Bucket rollupDateHistogramBucket = rollupDateHistogramBuckets.get(i);
                assertEquals(originalDateHistogramBucket.getKeyAsString(), rollupDateHistogramBucket.getKeyAsString());
                Aggregations originalAggregations = originalDateHistogramBucket.getAggregations();
                Aggregations rollupAggregations = rollupDateHistogramBucket.getAggregations();
                assertEquals(originalAggregations.asList().size(), rollupAggregations.asList().size());
                List<Aggregation> nonTopHitsOriginalAggregations = originalAggregations.asList()
                    .stream()
                    .filter(agg -> agg.getType().equals("top_hits") == false)
                    .toList();
                List<Aggregation> nonTopHitsRollupAggregations = rollupAggregations.asList()
                    .stream()
                    .filter(agg -> agg.getType().equals("top_hits") == false)
                    .toList();
                assertEquals(nonTopHitsOriginalAggregations, nonTopHitsRollupAggregations);
                List<Aggregation> topHitsOriginalAggregations = originalAggregations.asList()
                    .stream()
                    .filter(agg -> agg.getType().equals("top_hits"))
                    .toList();
                List<Aggregation> topHitsRollupAggregations = rollupAggregations.asList()
                    .stream()
                    .filter(agg -> agg.getType().equals("top_hits"))
                    .toList();
                assertEquals(topHitsRollupAggregations.size(), topHitsRollupAggregations.size());
                for (int j = 0; j < topHitsRollupAggregations.size(); ++j) {