fix: Correct Read The Docs build failures

[alexbenedicto]

Closes #114

This PR aims to correct the failures in the latest Read The Docs builds.
Specific packages when installing docs/requirements.txt caused conflicts because the python version used is 3.10.

The first solution was to upgrade to python 3.11 but this would not respect the supported versions 3.10 to 3.12 in the repository.
The second solution now applied in this PR is to restrict the version of specific packages.

PS:

1. xmlschema was added for geos-xml-viewer documentation.
2. A minor cleanup of autodoc_mock_imports was also added but would not have an impact on the resolution of the issue.
3. doc-test.yml updated to correctly catch future issues.

The first build that failed was after modifying these packages in the following commit de62e29 (see image):

[paloma-martinez]

Thank you for the fix !
Do you have an idea of what we could add to the CI to prevent this kind of problem ? It seems a lot of PR CI docs checks were valid while the actual buildings of the doc failed..

[alexbenedicto]

@paloma-martinez I updated the doc-test.yml to be matching the .readthedocs.yaml build so the CI should fail correctly now if the same issue occurs.