[CI] DataStreamIndexSettingsProviderTests testGetAdditionalIndexSettingsMappingsMerging failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic #11032 / encryption-at-rest
• elasticsearch-intake #29506 / part1
• elasticsearch-periodic #10969 / concurrent-search-tests
• elasticsearch-periodic #10962 / single-processor-node-tests

Reproduction Line:

./gradlew ":modules:data-streams:test" --tests "org.elasticsearch.datastreams.DataStreamIndexSettingsProviderTests.testGetAdditionalIndexSettingsMappingsMerging" -Dtests.seed=8921766E7DA7DE06 -Dtests.locale=xog-Latn-UG -Dtests.timezone=America/Indiana/Tell_City -Druntime.java=25

Applicable branches:
9.2

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: 
Expected: iterable with items ["field1", "field3"] in any order
     but: no item matches: "field1", "field3" in []

Issue Reasons:

• [9.2] 4 failures in test testGetAdditionalIndexSettingsMappingsMerging (1.6% fail rate in 252 executions)
• [9.2] 3 failures in pipeline elasticsearch-periodic (27.3% fail rate in 11 executions)

Note:
This issue was created using new test triage automation. Please report issues or feedback to es-delivery.

[elasticsearchmachine]

This has been muted on branch main

Mute Reasons:

• [main] 5 failures in test testGetAdditionalIndexSettingsMappingsMerging (1.0% fail rate in 526 executions)
• [main] 3 failures in step part-1 (1.2% fail rate in 247 executions)
• [main] 2 failures in pipeline elasticsearch-periodic (25.0% fail rate in 8 executions)
• [main] 3 failures in pipeline elasticsearch-pull-request (1.2% fail rate in 245 executions)

Build Scans:

• elasticsearch-periodic #10963 / openjdk24_checkpart1_java-matrix
• elasticsearch-pull-request #96516 / part-1
• elasticsearch-pull-request #96449 / part-1
• elasticsearch-pull-request #96129 / part-1
• elasticsearch-periodic #10918 / single-processor-node-tests

[elasticsearchmachine]

Pinging @elastic/es-storage-engine (Team:StorageEngine)

[elasticsearchmachine]

This has been muted on branch 9.2

Mute Reasons:

• [9.2] 4 failures in test testGetAdditionalIndexSettingsMappingsMerging (1.6% fail rate in 252 executions)
• [9.2] 3 failures in pipeline elasticsearch-periodic (27.3% fail rate in 11 executions)

Build Scans:

• elasticsearch-periodic #11032 / encryption-at-rest
• elasticsearch-intake #29506 / part1
• elasticsearch-periodic #10969 / concurrent-search-tests
• elasticsearch-periodic #10962 / single-processor-node-tests

[elasticsearchmachine]

Pinging @elastic/es-data-management (Team:Data Management)