Fixing ehcache flaky test

[sgup432]

Description

Fixing flaky test within EhcacheDiskCacheTests

Related Issues

#12758

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Failing checks are inspected and point to the corresponding known issue(s) (See: Troubleshooting Failing Builds)
• Commits are signed per the DCO using --signoff
• [ ] Commit changes are listed out in CHANGELOG.md file (See: Changelog)
• [ ] Public documentation issue/PR created

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[sgup432]

@reta Can you take a look at this one?

[github-actions]

Compatibility status:

Checks if related components are compatible with change 2155a48

Incompatible components

Skipped components

Compatible components

Compatible components: [https://github.com/opensearch-project/custom-codecs.git, https://github.com/opensearch-project/asynchronous-search.git, https://github.com/opensearch-project/neural-search.git, https://github.com/opensearch-project/flow-framework.git, https://github.com/opensearch-project/job-scheduler.git, https://github.com/opensearch-project/cross-cluster-replication.git, https://github.com/opensearch-project/reporting.git, https://github.com/opensearch-project/security-analytics.git, https://github.com/opensearch-project/geospatial.git, https://github.com/opensearch-project/opensearch-oci-object-storage.git, https://github.com/opensearch-project/k-nn.git, https://github.com/opensearch-project/notifications.git, https://github.com/opensearch-project/common-utils.git, https://github.com/opensearch-project/observability.git, https://github.com/opensearch-project/anomaly-detection.git, https://github.com/opensearch-project/ml-commons.git, https://github.com/opensearch-project/alerting.git, https://github.com/opensearch-project/index-management.git, https://github.com/opensearch-project/performance-analyzer-rca.git, https://github.com/opensearch-project/security.git, https://github.com/opensearch-project/sql.git, https://github.com/opensearch-project/performance-analyzer.git]

[github-actions]

✅ Gradle check result for 258159d: SUCCESS

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.46%. Comparing base (b15cb0c) to head (2155a48).
Report is 54 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #12764      +/-   ##
============================================
+ Coverage     71.42%   71.46%   +0.04%     
- Complexity    59978    60190     +212     
============================================
  Files          4985     4999      +14     
  Lines        282275   283036     +761     
  Branches      40946    41030      +84     
============================================
+ Hits         201603   202276     +673     
- Misses        63999    64012      +13     
- Partials      16673    16748      +75     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[github-actions]

❌ Gradle check result for 4af9ba8: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❕ Gradle check result for 2155a48: UNSTABLE

• TEST FAILURES:

      1 org.opensearch.cluster.allocation.ClusterRerouteIT.testDelayWithALargeAmountOfShards

Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

[sgup432]

@reta Build passed! Can you merge this? We will also need a backport 2.x label.