[CI] FilesEntitlementsValidationTests testValidationPass failing

[elasticsearchmachine]

Build Scans:

• elasticsearch-periodic #8326 / openjdk21_checkpart1_java-matrix
• elasticsearch-periodic #8326 / openjdk23_checkpart1_java-matrix
• elasticsearch-periodic #8326 / openjdk21_checkpart1_java-fips-matrix
• elasticsearch-periodic #8317 / openjdk21_checkpart1_java-fips-matrix
• elasticsearch-periodic #8317 / openjdk23_checkpart1_java-matrix
• elasticsearch-periodic #8317 / openjdk21_checkpart1_java-matrix
• elasticsearch-periodic #8311 / openjdk21_checkpart1_java-matrix
• elasticsearch-periodic #8311 / openjdk21_checkpart1_java-fips-matrix
• elasticsearch-periodic #8311 / openjdk23_checkpart1_java-matrix
• elasticsearch-periodic #8305 / openjdk21_checkpart1_java-matrix

Reproduction Line:

./gradlew ":libs:entitlement:test" --tests "org.elasticsearch.entitlement.initialization.FilesEntitlementsValidationTests.testValidationFailForRead" -Dtests.seed=99728E02EC1A8225 -Dtests.locale=ia-001 -Dtests.timezone=Asia/Pontianak -Druntime.java=21 -Dtests.fips.enabled=true

Applicable branches:
9.0

Reproduces locally?:
N/A

Failure History:
See dashboard

Failure Message:

junit.framework.AssertionFailedError: Unexpected exception type, expected IllegalArgumentException but got java.security.AccessControlException: access denied ("java.io.FilePermission" "/opt/buildkite-agent/.java/openjdk21/conf" "read")

Issue Reasons:

• [9.0] 21 consecutive failures in step openjdk21_checkpart1_java-matrix
• [9.0] 21 consecutive failures in step openjdk23_checkpart1_java-matrix
• [9.0] 22 consecutive failures in step openjdk21_checkpart1_java-fips-matrix
• [9.0] 64 failures in test testValidationPass (11.1% fail rate in 577 executions)
• [9.0] 21 failures in step openjdk21_checkpart1_java-matrix (100.0% fail rate in 21 executions)
• [9.0] 21 failures in step openjdk23_checkpart1_java-matrix (100.0% fail rate in 21 executions)
• [9.0] 22 failures in step openjdk21_checkpart1_java-fips-matrix (100.0% fail rate in 22 executions)
• [9.0] 22 failures in pipeline elasticsearch-periodic (100.0% fail rate in 22 executions)

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

[elasticsearchmachine]

Pinging @elastic/es-core-infra (Team:Core/Infra)

[ldematte]

Fixed by #128252