[BUG] [Flaky Test] S3BlobContainerRetriesTests is flaky

[peteralfonsi]

Describe the bug

Not sure why this didn't get an autocut. Looks like threads are leaking in org.opensearch.repositories.s3.S3BlobContainerRetriesTests.classMethod.

Example failures:
https://build.ci.opensearch.org/job/gradle-check/54203/testReport/junit/org.opensearch.repositories.s3/S3BlobContainerRetriesTests/classMethod_2/ (run from #17344)

https://build.ci.opensearch.org/job/gradle-check/54203/testReport/junit/org.opensearch.repositories.s3/S3BlobContainerRetriesTests/classMethod_2/ (run from #17513)

Related component

Build

To Reproduce

See linked jenkins builds

Expected behavior

Test should not be flaky.

Additional Details

[krisfreedain]

Catch All Triage - 1 2

[andrross]

Closing in favor of #17551