Fix flaky RemoteStoreStatsIT.testStatsOnShardUnassigned integ test

[shourya035]

Description

Fixing IT RemoteStoreStatsIT.testStatsOnShardUnassigned

Related Issues

Resolves #9036

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff
• Commit changes are listed out in CHANGELOG.md file (See: Changelog)

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[opensearch-trigger-bot]

Compatibility status:

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

BUILD SUCCESSFUL in 26m 1s

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: SUCCESS ✅
• URL: https://build.ci.opensearch.org/job/gradle-check/21695/
• CommitID: 260ae90