fix(sagemaker): Remove top-level sagemaker-ssh-kiro VSIX

[dylanraws]

Problem

1. Toolkit CI builds fail when they detect more than one VSIX file at the top level, due to the sagemaker-ssh-kiro extension being present even though it's not needed there
2. Whenever the sagemaker-ssh-kiro extension version is updated (e.g., 0.2.0 -> 0.3.0), there can be two VSIX files in the toolkit resources directory, which can eventually lead to an error as the toolkit cannot determine which file to install at runtime

Solution

1. As part of packaging toolkit, move (rather than copy) the sagemaker-ssh-kiro VSIX file to the toolkit resources directory, so that it will be no longer present at the top level, thus preventing any CI build failures
2. Remove all sagemaker-ssh-kiro VSIX files from the toolkit resources directory before moving the new file there

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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]

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[amazon-inspector-ohio]

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