It looks like this suite timed out because a node of the backing cluster exploded. Looks like an assertion was tripped.

```
» [2023-10-09T21:16:07,555][ERROR][o.e.b.ElasticsearchUncaughtExceptionHandler] [v8.8.2-2] fatal error in thread [elasticsearch[v8.8.2-2][clusterApplierService#updateTask][T#1]], exiting java.lang.AssertionError: provided source [{"_doc":{"_data_stream_timestamp":{"enabled":true},"_source":{"mode":"synthetic"},"properties":{"@timestamp":{"type":"date"},"key":{"type":"keyword","time_series_dimension":true}}}}] differs from mapping [{"_doc":{"_data_stream_timestamp":{"enabled":true},"properties":{"@timestamp":{"type":"date"},"key":{"type":"keyword","time_series_dimension":true}}}}]
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.index.mapper.DocumentMapper.<init>(DocumentMapper.java:42)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.index.mapper.MapperService.newDocumentMapper(MapperService.java:376)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.index.mapper.MapperService.updateMapping(MapperService.java:285)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.index.IndexService.updateMapping(IndexService.java:700)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.indices.cluster.IndicesClusterStateService.createIndicesAndUpdateShards(IndicesClusterStateService.java:493)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.indices.cluster.IndicesClusterStateService.applyClusterState(IndicesClusterStateService.java:250)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.cluster.service.ClusterApplierService.callClusterStateAppliers(ClusterApplierService.java:536)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.cluster.service.ClusterApplierService.callClusterStateAppliers(ClusterApplierService.java:522)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.cluster.service.ClusterApplierService.applyChanges(ClusterApplierService.java:495)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.cluster.service.ClusterApplierService.runTask(ClusterApplierService.java:426)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.cluster.service.ClusterApplierService$UpdateTask.run(ClusterApplierService.java:154)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingRunnable.run(ThreadContext.java:916)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.runAndClean(PrioritizedEsThreadPoolExecutor.java:217)
»  	at org.elasticsearch.server@8.8.2/org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.run(PrioritizedEsThreadPoolExecutor.java:183)
»  	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
»  	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
»  	at java.base/java.lang.Thread.run(Thread.java:1623)
»  
»  
»  ERROR: Elasticsearch exited unexpectedly
```

**Build scan:**
https://gradle-enterprise.elastic.co/s/bte5oskoqsjl6/tests/:qa:mixed-cluster:v8.8.2%23mixedClusterTest/org.elasticsearch.backwards.MixedClusterClientYamlTestSuiteIT
**Reproduction line:**
```
null
```

**Applicable branches:**
main

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

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.backwards.MixedClusterClientYamlTestSuiteIT&tests.test=classMethod
**Failure excerpt:**
```
java.lang.Exception: Suite timeout exceeded (>= 2400000 msec).

  at __randomizedtesting.SeedInfo.seed([E230389699262455]:0)

```
server/src/test/java/org/elasticsearch/index/query/SearchExecutionContextTests.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.index.query;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.KeywordField;
import org.apache.lucene.document.StringField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.memory.MemoryIndex;
import org.apache.lucene.search.Collector;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.LeafCollector;