Remove mapping for 'src' to 'auto-mix-prep'

[XanthanGum]

📝 Summary

Remove package mapping 'src' to an unmaintained package 'auto-mix-prep'.
Package is available on pypi, however link to repository is broken.

src is commonly used as a python module folder, and users trying to import their own modules instead under src.X raise a module not not found error, pointing to auto-mix-prep, and are prompted to install with UV.

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Project	Deployment	Actions	Updated (UTC)
marimo-docs	Ready	Preview, Comment	May 29, 2026 1:54pm

[XanthanGum]

I have read the CLA Document and I hereby sign the CLA

[github-actions]

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[Light2Dark]

I'm okay to remove this, since the name doesn't match.
However, if you do have a module/folder locally called src, it should not trigger the installation prompt