Invalid documentation URLs on PyPI

[fmigneault]

🐛 Bug Report

All relative references to local files or anchors within the README do no resolve on https://pypi.org/project/stac-model/.

For example, the Best Practices link points at https://pypi.org/project/stac-model/best-practices.md instead of https://github.com/crim-ca/mlm-extension/blob/main/best-practices.md.

Anchors like #task-enum points at https://pypi.org/project/stac-model/#task-enum, which does not resolve because PyPI does not seem to generate the link references for the header sections.

🔬 How To Reproduce

Steps to reproduce the behavior:

1. Go on the PyPI page.
2. Click any link referring to contents hosted by this repository.

📈 Expected behavior

All relative links should be updated with explicit URL to the files so they are resolved correctly, no matter where the README source is hosted from.