Update repository references from 'encode' to 'Kludex'

[secrett2633]

Summary

Replaced all references of encode/uvicorn with Kludex/uvicorn to reflect the recent repository transfer of Uvicorn from the Encode to @Kludex. Kludex/starlette#2997

Checklist

• I understand that this PR may be closed in case there was no previous discussion. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.

[Kludex]

Thanks @secrett2633 🙏