Docs: Interactive builds loop

[medubelko]

Bug Description

As I covered recently, interactive builds run in an infinite loop.

To Reproduce

1. Run:

   tox run -e autobuild-docs

   After it first builds, no issues are detected.
2. Save a change to any RST file in /docs. The docs begin rebuilding in a loop.

Environment

System: Ubuntu 24.04
Environment: Snapcraft repo, no LXD/Multipass setup.

snapcraft.yaml

-

Relevant log output

[sphinx-autobuild] Detected change. Rebuilding...
[sphinx-autobuild] > sphinx-build -b html /home/med/dev/snapcraft/docs /home/med/dev/snapcraft/docs/_build

Additional context

@tigarmo This might be related to importing docs inside of other docs. Another TA reported similar issues a few months ago and their temporary solution was to exclude some of the content from rebuild. We found others that vouch for this being a possibility: sphinx-doc/sphinx#11556 (comment). I haven't looked into this deeply, though.

If we could get sphinx-autobuild to specify what files it detects have changed, this would be easier to diagnose, but even with the -v option it merely says Detected change.