fix: Fix race condition in model loading/unloading in Sagemaker server

[yinggeh]

What does the PR do?

Fix race condition causing segfault in model loading/unloading in Sagemaker server.

Checklist

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• Related issues are referenced.
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Commit Type:

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• fix

Related PRs:

Where should the reviewer start?

Test plan:

L0_sagemaker--base

• CI Pipeline ID:
  40037063

Caveats:

Background

Related Issues: (use one of the action keywords Closes / Fixes / Resolves / Relates to)

• closes GitHub issue: #xxx