[CI] MergeWithFailureIT testFailedMergeDeadlock failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic #10821 / openjdk21_checkpart1_java-fips-matrix
• elasticsearch-pull-request #94721 / part-1

Reproduction Line:

./gradlew ":server:internalClusterTest" --tests "org.elasticsearch.index.engine.MergeWithFailureIT.testFailedMergeDeadlock" -Dtests.seed=491670C0A0ECB01B -Dtests.locale=lkt-US -Dtests.timezone=America/Atka -Druntime.java=21 -Dtests.fips.enabled=true

Applicable branches:
main

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

java.lang.AssertionError: null

Issue Reasons:

• [main] 2 failures in test testFailedMergeDeadlock (0.7% fail rate in 296 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] 2 failures in test testFailedMergeDeadlock (0.7% fail rate in 296 executions)

Build Scans:

• elasticsearch-periodic #10821 / openjdk21_checkpart1_java-fips-matrix
• elasticsearch-pull-request #94721 / part-1

[elasticsearchmachine]

Pinging @elastic/es-distributed-indexing (Team:Distributed Indexing)