Added static setting for checkPendingFlushUpdate functionality of lucene index writer

[CaptainDredge]

Description

This PR exposes the setting index.check_pending_flush.enabled setting to control lucene index writer checkPendingFlushOnUpdate

Related Issues

Resolves #11628

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.

[github-actions]

Compatibility status:

Checks if related components are compatible with change b9593db

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/anomaly-detection.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/opensearch-oci-object-storage.git, https://github.com/opensearch-project/geospatial.git, https://github.com/opensearch-project/common-utils.git, https://github.com/opensearch-project/k-nn.git, https://github.com/opensearch-project/alerting.git, https://github.com/opensearch-project/neural-search.git, https://github.com/opensearch-project/security-analytics.git, https://github.com/opensearch-project/performance-analyzer-rca.git, https://github.com/opensearch-project/notifications.git, https://github.com/opensearch-project/index-management.git, https://github.com/opensearch-project/ml-commons.git, https://github.com/opensearch-project/security.git, https://github.com/opensearch-project/observability.git, https://github.com/opensearch-project/performance-analyzer.git, https://github.com/opensearch-project/sql.git]

[github-actions]

❌ Gradle check result for 8d17786: ABORTED

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 36a7c7e: 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 b9593db: UNSTABLE

• TEST FAILURES:

      1 org.opensearch.search.SearchWeightedRoutingIT.testStrictWeightedRoutingWithCustomString_FailOpenEnabled
      1 org.opensearch.repositories.azure.AzureBlobContainerRetriesTests.testWriteLargeBlob

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

[CaptainDredge]

TEST FAILURES:
1 org.opensearch.search.SearchWeightedRoutingIT.testStrictWeightedRoutingWithCustomString_FailOpenEnabled
1 org.opensearch.repositories.azure.AzureBlobContainerRetriesTests.testWriteLargeBlob
Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

Flaky tests failing

• [BUG] SearchWeightedRoutingIT.testStrictWeightedRoutingWithCustomString_FailOpenEnabled is flaky #12708
• [BUG] org.opensearch.repositories.azure.AzureBlobContainerRetriesTests.testWriteLargeBlob test is flaky #12651

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/OpenSearch/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.x
# Create a new branch
git switch --create backport/backport-12710-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 c369ec44e381ddb85db647d89389842952a1c06a
# Push it to GitHub
git push --set-upstream origin backport/backport-12710-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-12710-to-2.x.

[reta]

@CaptainDredge could you please backport to 2.x manually? Thank you

[CaptainDredge]

@CaptainDredge could you please backport to 2.x manually? Thank you

sure @reta

[reta]

@CaptainDredge please don't forget to update documentation [1] with this new setting, thank you

[1] https://github.com/opensearch-project/documentation-website/issues

[CaptainDredge]

Thanks @reta Already the PR for documentation is open. I'm hoping a doc writer in US timing will merge it
opensearch-project/documentation-website#6728