Summary

sphinx-pyrunblock is Peter's own package (a hard fork of the original WhyNotHugo/sphinx-autorun, published properly to PyPI under this name). Today's CI installs it via pip install git+https://github.com/petercorke/sphinx-autorun.git -- an old, pre-rename URL that still works only because GitHub redirects renamed repos. This switches to installing the plain PyPI wheel instead.

• Bumps pyproject.toml's docs extra from "sphinx-autorun" to "sphinx-pyrunblock" (the old entry was misleading in isolation -- without the workflow's follow-up git install, it would resolve to the unrelated upstream PyPI package of the same name, not Peter's fork).
• Drops the now-redundant pip install git+... line from sphinx.yml, since pip install .[dev,docs] already installs the right package.
• Updates conf.py's extensions list from sphinx_autorun to sphinx_pyrunblock to match.

No functional change

Both the old git URL and the new PyPI package resolve to the identical sphinx-pyrunblock==1.1.0 release today -- confirmed with a fresh, uncached pip install git+... and comparing installed package metadata. This is purely a speed/hygiene change.

Why

The PyPI install is consistently 2-4x faster in a clean venv (no git clone/VCS metadata resolution):

That's ~9-15s saved on every docs-build CI run (every push to master plus every PR).

Test plan

• Fresh isolated venv, pip install ".[dev,docs]", confirmed sphinx-pyrunblock==1.1.0 resolves without the git install line
• Real sphinx-build -b html against the rebased branch (includes perf: defer Matplotlib import until something actually plots #198, Fix sphinx automation #162) -- succeeds, 15 warnings, consistent with pre-change baseline