DOC: README Not present or not working urls

Problem

On README there are some written files like ./requirements.txt, ./test-requirements.txt, ./pyproject.toml... without a url that points directly to themselves.
There is also a file where there is a link but it is a relative url, making it not work on PyPI

Reproduction of the problem

For the first case: go on PyPI page or Github repository, and see for the examples I brought up that they have no url.

For the second case: go on PyPI page, on LICENCE section and press on the clickable text "a separate license, detailed here", the relative link goes in a 404 page.