Update sphinx requirement from <8 to <9

[dependabot]

Updates the requirements on sphinx to permit the latest version.

Release notes

Sourced from sphinx's releases.

Sphinx 8.1.3

Changelog: https://www.sphinx-doc.org/en/master/changes.html

Bugs fixed

• #13013: Restore support for cut_lines() with no object type. Patch by Adam Turner.

Changelog

Sourced from sphinx's changelog.

Release 8.1.3 (in development)

Bugs fixed

• #13013: Restore support for :func:!cut_lines with no object type. Patch by Adam Turner.

Release 8.1.2 (released Oct 12, 2024)

Bugs fixed

• #13012: Expose :exc:sphinx.errors.ExtensionError in sphinx.util for backwards compatibility. This will be removed in Sphinx 9, as exposing the exception in sphinx.util was never intentional. :exc:!ExtensionError has been part of sphinx.errors since Sphinx 0.9. Patch by Adam Turner.

Release 8.1.1 (released Oct 11, 2024)

Bugs fixed

• #13006: Use the preferred https://www.cve.org/ URL for the :rst:role::cve: <cve> role. Patch by Hugo van Kemenade.
• #13007: LaTeX: Improve resiliency when the required fontawesome or fontawesome5 packages are not installed. Patch by Jean-François B.

Release 8.1.0 (released Oct 10, 2024)

Dependencies

• #12756: Add lower-bounds to the sphinxcontrib-* dependencies. Patch by Adam Turner.
• #12833: Update the LaTeX parskip package from 2001 to 2018. Patch by Jean-François B.

Incompatible changes

• #12763: Remove unused internal class sphinx.util.Tee.

... (truncated)

Commits

• a1510de Bump to 8.1.3 final
• 62e9606 Restore support for cut_lines() with no object type (#13015)
• 5ae32ce Bump version
• a72b47b Bump to 8.1.2 final
• 39a45ad Expose ExtensionError in sphinx.util for backwards compatibility.
• 5a4859a Add docs about sphinx-autobuild (#13011)
• 05679ef Type-check the 'autodoc_intenum' example (#12827)
• 86d1d31 Prune CHANGES of unneeded sections
• b6269d3 Improve documentation for the Builder API (#13008)
• c46abc4 Improve clarity for master_doc and root_doc
• Additional commits viewable in compare view

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[zerothi]

This can't be merged, there are some problems in the nbpshinx + sphinx changes that crashes.

The problem relates to the fact that the sphinx API changes _StrPath to pathlib.Path, thus requiring everything to change behaviour... This is recognized by nbsphinx and currentlyt they think it is solved, but it is not. The log looks something like this:

# Platform:         linux; (Linux-6.1.0-26-amd64-x86_64-with-glibc2.36)
# Sphinx version:   8.1.3
# Python version:   3.11.7 (CPython)
# Docutils version: 0.21.2
# Jinja2 version:   3.1.4
# Pygments version: 2.18.0

# Last messages:
#   quickstart/index
#   
#   
#   reading sources... [ 89%]
#   quickstart/install
#   
#   
#   reading sources... [ 90%]
#   quickstart/intro_tutorials/01_geometry
#   

# Loaded extensions:
#   sphinx.ext.mathjax (8.1.3)
#   alabaster (1.0.0)
#   sphinxcontrib.applehelp (2.0.0)
#   sphinxcontrib.devhelp (2.0.0)
#   sphinxcontrib.htmlhelp (2.1.0)
#   sphinxcontrib.serializinghtml (2.0.0)
#   sphinxcontrib.qthelp (2.0.0)
#   sphinx.ext.autodoc.preserve_defaults (8.1.3)
#   sphinx.ext.autodoc.type_comment (8.1.3)
#   sphinx.ext.autodoc.typehints (8.1.3)
#   sphinx.ext.autodoc (8.1.3)
#   sphinx.ext.autosummary (8.1.3)
#   sphinx.ext.intersphinx (8.1.3)
#   sphinx.ext.extlinks (8.1.3)
#   sphinx.ext.napoleon (8.1.3)
#   sphinx.ext.todo (8.1.3)
#   sphinx.ext.viewcode (8.1.3)
#   sphinx_togglebutton (0.3.2)
#   sphinx_copybutton (0.5.2)
#   sphinx_design (0.6.1)
#   sphinxcontrib.jquery (4.1)
#   sphinx_inline_tabs (2023.04.21)
#   matplotlib.sphinxext.plot_directive (3.7.1)
#   IPython.sphinxext.ipython_directive (unknown version)
#   IPython.sphinxext.ipython_console_highlighting (unknown version)
#   sphinx.ext.graphviz (8.1.3)
#   sphinx.ext.inheritance_diagram (8.1.3)
#   nbsphinx (0.9.5)
#   sphinx_gallery.load_style (0.18.0)
#   sphinxcontrib.bibtex (2.6.3)
#   sphinx_rtd_theme (unknown version)

# Traceback:
Traceback (most recent call last):
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/cmd/build.py", line 514, in build_main
    app.build(args.force_all, args.filenames)
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/application.py", line 381, in build
    self.builder.build_update()
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/builders/__init__.py", line 358, in build_update
    self.build(
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/builders/__init__.py", line 385, in build
    updated_docnames = set(self.read())
                           ^^^^^^^^^^^
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/builders/__init__.py", line 502, in read
    self._read_serial(docnames)
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/builders/__init__.py", line 567, in _read_serial
    self.read_doc(docname)
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/builders/__init__.py", line 630, in read_doc
    publisher.publish()
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/docutils/core.py", line 234, in publish
    self.document = self.reader.read(self.source, self.parser,
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/sphinx/io.py", line 106, in read
    self.parse()
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/docutils/readers/__init__.py", line 76, in parse
    self.parser.parse(self.input, document)
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/nbsphinx/__init__.py", line 667, in parse
    env.config.nbsphinx_prolog).render(env=env)
                                ^^^^^^^^^^^^^^^
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/jinja2/environment.py", line 1304, in render
    self.environment.handle_exception()
  File "/home/nicpa/codes/sisl/docs/.venv-docs/lib/python3.11/site-packages/jinja2/environment.py", line 939, in handle_exception
    raise rewrite_traceback_stack(source=source)
  File "<template>", line 2, in top-level template code
TypeError: can only concatenate str (not "_StrPath") to str

[zerothi]

@dependabot rebase