[Backport 2.x] Fix for race condition in node-join/node-left loop

[opensearch-trigger-bot]

Backport 1563e1a from #15521.

[github-actions]

❌ Gradle check result for 83ea071: 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 83ea071: UNSTABLE

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

Attention: Patch coverage is 88.09524% with 5 lines in your changes missing coverage. Please review.

Project coverage is 71.77%. Comparing base (b180569) to head (83ea071).
Report is 7 commits behind head on 2.x.

Files with missing lines	Patch %	Lines
.../opensearch/transport/RemoteConnectionManager.java	0.00%	4 Missing ⚠️
...g/opensearch/cluster/coordination/Coordinator.java	88.88%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x   #16118      +/-   ##
============================================
- Coverage     71.79%   71.77%   -0.02%     
- Complexity    64798    64813      +15     
============================================
  Files          5278     5278              
  Lines        302676   302713      +37     
  Branches      44037    44038       +1     
============================================
- Hits         217303   217277      -26     
- Misses        67226    67312      +86     
+ Partials      18147    18124      -23     

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