fix(sagemaker): Adjust retry configuration for StartSession

[dylanraws]

Problem

When a user tries to connect to a SageMaker Space that is in the Stopped status (i.e., the underlying App is Deleted or has not been created), the Space will be automatically started by the toolkit before the connection is attempted. In some cases, the Space reaches the Running status (i.e., the App reaches the InService status) but the remote access capability is not yet ready as it starts asynchronously, leading to the SageMaker:StartSession API receiving an Internal Failure response. The client already retries, but the retries happen too quickly, before remote access becomes ready.

Solution

Adjust the SageMaker client retry configuration for StartSession calls made from the detached server (called via the sagemaker_connect script) to spread out the retries over multiple seconds.

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[amazon-inspector-ohio]

⏳ I'm reviewing this pull request for security vulnerabilities and code quality issues. I'll provide an update when I'm done

[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
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[amazon-inspector-ohio]

✅ I finished the code review, and didn't find any security or code quality issues.

[vpbhargav]

Thanks for the fix! Hope we tested across both SM AI and SMUS to ensure no regressions as well.

[laileni-aws]

/retryBuilds