readthedocs.io API Reference only shows headings as of 3.1.15

Currently, the API reference section for GitPython on readthedocs.io just shows the headings:

This is happening for version 3.1.15, "stable", and "latest":

• https://gitpython.readthedocs.io/en/3.1.15/reference.html
• https://gitpython.readthedocs.io/en/stable/reference.html
• https://gitpython.readthedocs.io/en/latest/reference.html

3.1.14 looks fine, however:

https://gitpython.readthedocs.io/en/3.1.14/reference.html

it seems like something about the autodocs changed between 3.1.14 and 3.1.15