[CI] SearchWithIndexBlocksIT testSearchShardsOnIndicesWithIndexRefreshBlocks failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic-platform-support #9535 / rhel-9_platform-support-unix
• elasticsearch-intake #25869 / part1
• elasticsearch-pull-request #82068 / part-1
• elasticsearch-periodic #9517 / openjdk21_checkpart1_java-matrix
• elasticsearch-periodic-platform-support #9528 / amazonlinux-2023_platform-support-aws
• elasticsearch-periodic-platform-support #9528 / oraclelinux-9_platform-support-unix

Reproduction Line:

./gradlew ":server:internalClusterTest" --tests "org.elasticsearch.search.SearchWithIndexBlocksIT.testSearchShardsOnIndicesWithIndexRefreshBlocks" -Dtests.seed=B5BCA1CEBF327A67 -Dtests.locale=ce-RU -Dtests.timezone=Africa/Abidjan -Druntime.java=24

Applicable branches:
main

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: null

Issue Reasons:

• [main] 6 failures in test testSearchShardsOnIndicesWithIndexRefreshBlocks (9.1% fail rate in 66 executions)
• [main] 2 failures in pipeline elasticsearch-periodic-platform-support (100.0% fail rate in 2 executions)

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

[elasticsearchmachine]

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

[javanna]

@benchaplin this is the test you recently added :)

[elasticsearchmachine]

This has been muted on branch main

Mute Reasons:

• [main] 5 failures in test testSearchShardsOnIndicesWithIndexRefreshBlocks (8.2% fail rate in 61 executions)

Build Scans:

• elasticsearch-intake #25869 / part1
• elasticsearch-pull-request #82068 / part-1
• elasticsearch-periodic #9517 / openjdk21_checkpart1_java-matrix
• elasticsearch-periodic-platform-support #9528 / amazonlinux-2023_platform-support-aws
• elasticsearch-periodic-platform-support #9528 / oraclelinux-9_platform-support-unix