Support for PyPy3 removed

Starting on July 18, 2023 PyPy3 will be removed as an option to build documentation on Read the Docs.

This feature was introduced as an alternative to make Sphinx build faster. However, we found there are no projects building their documentation with PyPy3 and we decided to remove its support to simplify our product and reduce development maintanence.

Please, contact us and let us know if you require PyPy3 to build your documentation.