Bump sphinx-autobuild from 2021.3.14 to 2024.4.16

Bumps [sphinx-autobuild](https://github.com/sphinx-doc/sphinx-autobuild) from 2021.3.14 to 2024.4.16.
- [Release notes](https://github.com/sphinx-doc/sphinx-autobuild/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx-autobuild/blob/main/NEWS.rst)
- [Commits](sphinx-doc/sphinx-autobuild@2021.03.14...2024.04.16)

---
updated-dependencies:
- dependency-name: sphinx-autobuild
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

setup.py

@@ -28,7 +28,7 @@
     "poethepoet<0.27",
     "pyproject-fmt<2.2",
     "ruff<0.5",
-    "sphinx-autobuild==2021.3.14",  # Newer versions stopped "watching" appropriately?
+    "sphinx-autobuild==2024.4.16",  # Newer versions stopped "watching" appropriately?
     "validate-pyproject<0.19",
 ]