quickfix: removing cells that hardcoded role in notebook

[dwarez]

Note

Low Risk
Documentation-only notebook edit with no runtime or security logic changes in application code.

Overview
Removes a code cell in the SageMaker embedding deployment notebook that hardcoded role to a specific AWS account IAM ARN (754289655784).

Readers now rely on the existing setup cell that resolves the role via get_execution_role() (or the sagemaker_execution_role fallback), so the notebook works in their own account without copying a foreign role ARN.

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[HuggingFaceDocBuilderDev]

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