fix: remove nonexistent sys-stdout dependency (dependency confusion)

[x4v13r64]

sys-stdout in Pipfile is not a registered PyPI package — it conflates sys.stdout (Python's standard output stream object) with an installable package name. It is not needed for the bootstrapper's functionality.

Any attacker who registers sys-stdout on PyPI would have their package installed into an environment with active Google Cloud credentials and SA360 data pipeline access.

This PR removes the sys-stdout entry from Pipfile.

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