[Backport 2.x] Fix flaky test **/testSearchTaskCancellationWithHighCpu & shard variant

[opensearch-trigger-bot]

Backport 812b3e3 from #7978.

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: FAILURE ❌
• URL: https://build.ci.opensearch.org/job/gradle-check/17225/
• CommitID: 3a480e6
  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?

[reta]

• URL: https://build.ci.opensearch.org/job/gradle-check/17225/

#7746 :(

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: FAILURE ❌
• URL: https://build.ci.opensearch.org/job/gradle-check/17230/
• CommitID: 3a480e6
  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 (Jenkins) Run Completed with:

• RESULT: UNSTABLE ❕
• TEST FAILURES:

      1 org.opensearch.repositories.azure.AzureBlobContainerRetriesTests.testReadNonexistentBlobThrowsNoSuchFileException

• URL: https://build.ci.opensearch.org/job/gradle-check/17232/
• CommitID: 3a480e6
  Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

[codecov]

Codecov Report

Merging #7987 (3a480e6) into 2.x (bb4883b) will decrease coverage by 0.03%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##                2.x    #7987      +/-   ##
============================================
- Coverage     70.57%   70.55%   -0.03%     
- Complexity    56545    56571      +26     
============================================
  Files          4681     4681              
  Lines        268162   268162              
  Branches      39669    39669              
============================================
- Hits         189249   189190      -59     
- Misses        62642    62712      +70     
+ Partials      16271    16260      -11     

see 443 files with indirect coverage changes