[CI] SearchHitsTests testConcurrentEquals failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #8320 / ubuntu-2004-aarch64_checkpart1_platform-support-arm
• elasticsearch-periodic-platform-support #8278 / ubuntu-2004-aarch64_checkpart1_platform-support-arm

Reproduction Line:

./gradlew ":server:test" --tests "org.elasticsearch.search.SearchHitsTests.testConcurrentEquals" -Dtests.seed=8FE8D9203AB75971 -Dtests.locale=sw-UG -Dtests.timezone=Africa/Bamako -Druntime.java=24

Applicable branches:
8.19

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: expected: org.elasticsearch.search.SearchHits<org.elasticsearch.search.SearchHits@27169a20> but was: org.elasticsearch.search.SearchHits<org.elasticsearch.search.SearchHits@27169a20>

Issue Reasons:

• [8.19] 2 failures in test testConcurrentEquals (0.7% fail rate in 294 executions)
• [8.19] 2 failures in step ubuntu-2004-aarch64_checkpart1_platform-support-arm (25.0% fail rate in 8 executions)
• [8.19] 2 failures in pipeline elasticsearch-periodic-platform-support (25.0% fail rate in 8 executions)

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

[elasticsearchmachine]

Pinging @elastic/es-search (Team:Search)

[elasticsearchmachine]

Pinging @elastic/es-search-foundations (Team:Search Foundations)