Tests relies on nonexistant sphinx.testing.path which was deprecated in Sphinx 7.2

[apteryks]

Describe the bug

context
When I run pytest

expectation
Test suites run and passes.

bug
But instead it fails
Here's an error message I ran into:

ImportError while loading conftest '/tmp/guix-build-python-sphinx-multitoc-numbering-0.1.3.drv-0/source/tests/conftest.py'.
tests/conftest.py:3: in <module>
    from sphinx.testing.path import path
E   ModuleNotFoundError: No module named 'sphinx.testing.path'

problem
Can't run the test suite with a modern Sphinx version.

Reproduce the bug

Run pytest.

List your environment

Python 3.12 with inputs python-pytest@9.0.2 python-setuptools@80.9.0 python-sphinx@9.0.3.