Update dependencies for GH Actions

Author: ethanc8

.github/workflows/sphinx.yml

@@ -12,7 +12,7 @@ jobs:
     - name: Build HTML
       uses: ammaraskar/sphinx-action@master
       with:
-        pre-build-command: "pip3 install --user --ignore-installed sphinxcontrib-domaintools myst-parser furo sphinx>=6.0 sphinx_design sphinx-copybutton"
+        pre-build-command: "pip3 install --user --ignore-installed sphinxcontrib-domaintools myst-parser furo pydata-sphinx-theme sphinx>=8.0 sphinx_design sphinx-copybutton"
         docs-folder: .
     - name: Upload artifacts
       uses: actions/upload-artifact@v4