Build is failing with Sphinx version error

[tompollard]

The current build of the website is failing. See:
https://github.com/wfdb/mimic_wfdb_tutorials/actions/runs/10009960994

Running Jupyter-Book v0.9.1
Source Folder: /home/runner/work/mimic_wfdb_tutorials/mimic_wfdb_tutorials/content
Config Path: /home/runner/work/mimic_wfdb_tutorials/mimic_wfdb_tutorials/content/_config.yml
Output Path: /home/runner/work/mimic_wfdb_tutorials/mimic_wfdb_tutorials/content/_build/html
Running Sphinx v3.5.4

Sphinx version error:
The sphinxcontrib.applehelp extension used by this project needs at least Sphinx v5.0; it therefore cannot be built with this version.
Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/sphinx/registry.py", line 430, in load_extension
    metadata = setup(app)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/sphinxcontrib/applehelp/__init__.py", line 230, in setup
    app.require_sphinx('5.0')
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/sphinx/application.py", line 415, in require_sphinx
    raise VersionRequirementError(version)
sphinx.errors.VersionRequirementError: 5.0

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/jupyter_book/sphinx.py", line 112, in build_sphinx
    app = Sphinx(
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/sphinx/application.py", line 241, in __init__
    self.setup_extension(extension)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/sphinx/application.py", line 402, in setup_extension
    self.registry.load_extension(self, extname)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/sphinx/registry.py", line 433, in load_extension
    raise VersionRequirementError(
sphinx.errors.VersionRequirementError: The sphinxcontrib.applehelp extension used by this project needs at least Sphinx v5.0; it therefore cannot be built with this version.

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.9.19/x64/bin/jupyter-book", line [8](https://github.com/wfdb/mimic_wfdb_tutorials/actions/runs/10009960994/job/27670031010#step:5:9), in <module>
    sys.exit(main())
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.[9](https://github.com/wfdb/mimic_wfdb_tutorials/actions/runs/10009960994/job/27670031010#step:5:10)/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/click/core.py", line [10](https://github.com/wfdb/mimic_wfdb_tutorials/actions/runs/10009960994/job/27670031010#step:5:11)78, in main
    rv = self.invoke(ctx)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/click/core.py", line [14](https://github.com/wfdb/mimic_wfdb_tutorials/actions/runs/10009960994/job/27670031010#step:5:15)34, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/jupyter_book/commands/__init__.py", line 303, in build
    builder_specific_actions(
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/jupyter_book/commands/__init__.py", line 545, in builder_specific_actions
    raise RuntimeError(_message_box(msg, color="red", doprint=False)) from result
RuntimeError: 
===============================================================================

There was an error in building your book. Look above for the cause.

===============================================================================

Error: Process completed with exit code 1.