Build failure if Docutils version is 0.18 (not 0.18.1) due to missing Node.findall()

[jfbu]

Describe the bug

Exception occurred:
  File "/Users/path/to/sphinx/sphinx/transforms/__init__.py", line 204, in apply
    for node in self.document.findall():  # type: Node
AttributeError: 'document' object has no attribute 'findall'

How to Reproduce

pip install docutils==0.18

then attempt make html on any Sphinx project.

Expected behavior

No error

Your project

any

Screenshots

No response

OS

Mac

Python version

3.10.4

Sphinx version

Sphinx v5.1.0+/1786e989c

Sphinx extensions

No response

Extra tools

No response

Additional context

#10044 prepared the migration. But the Docutils 0.18 (which does not have Nodes.findall() ) is not detected:

sphinx/sphinx/util/docutils.py

Lines 552 to 559 in 20f52d9

	# Node.findall() is a new interface to traverse a doctree since docutils-0.18.
	# This applies a patch docutils-0.17 or older to be available Node.findall()
	# method to use it from our codebase.
	if docutils.__version_info__ < (0, 18):
	def findall(self, *args, **kwargs):
	return iter(self.traverse(*args, **kwargs))
	Node.findall = findall # type: ignore

The Docutils revision 8885 is part of Docutils 0.18.1 not of 0.18.

People with Docutils version exactly at 0.18 (which is available on pypi) and Sphinx 4.4.0 and later will encounter the problem. Perhaps very few people will be in this situation, as 0.18.1 was released about one month after 0.18.

[AA-Turner]

Closed in #10597

A