warning: bad-index-doctype on configuring

[AyanSinhaMahapatra]

warning: bad-index-doctype

× The package index page being used does not have a proper HTML doctype declaration.
╰─> Problematic URL: https://thirdparty.aboutcode.org/pypi/simple/pip/

note: This is an issue with the page at the URL mentioned above.
hint: You might need to reach out to the owner of that package index, to get this fixed. See https://github.com/pypa/pip/issues/10825 for context.

See pypa/pip#10825