v0.3.0 - Fix RTD

What's Changed

• Update Actions and python & sphinx matrix by @sciencewhiz in #9
• Actually test with matrix sphinx version by @sciencewhiz in #11
• Use RTD environment variables instead of html_context by @sciencewhiz in #10
• Test with Sphinx 8 and Python 3.13 by @sciencewhiz in #12
• Update Sphinx version in README by @sciencewhiz in #13

New Contributors

• @sciencewhiz made their first contribution in #9

Full Changelog: 0.2.0...0.3.0