Bump nbsphinx from 0.9.3 to 0.9.4 (#606)

Bumps [nbsphinx](https://github.com/spatialaudio/nbsphinx) from 0.9.3 to 0.9.4.
- [Release notes](https://github.com/spatialaudio/nbsphinx/releases)
- [Changelog](https://github.com/spatialaudio/nbsphinx/blob/master/NEWS.rst)
- [Commits](spatialaudio/nbsphinx@0.9.3...0.9.4)

---
updated-dependencies:
- dependency-name: nbsphinx
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

pyproject.toml

@@ -42,7 +42,7 @@ docs = [
     "furo==2024.5.6",
     "ipython==8.23.0",
     "myst_parser==2.0.0",
-    "nbsphinx==0.9.3",
+    "nbsphinx==0.9.4",
     "sphinx-copybutton==0.5.2",
     "sphinx==7.3.7",
 ]