Tests fail with the latest versions of sphinx

[Yannick-Dayer]

auto-intersphinx tests work with sphinx=7.4 but fail with sphinx=8.0

[Yannick-Dayer]

Ah, it seems to be an issue with the output of sphinx. Here is an output that we fail to parse:

Running Sphinx v8.0.2                                                                                                                                                                          
loading translations [en]... done                                                                                                                                                              
making output directory... done                                                                                                                                                                
Converting `source_suffix = '.rst'` to `source_suffix = {'.rst': 'restructuredtext'}`.                                                                                                         
loading intersphinx inventory 'python' from https://docs.python.org/3.10//objects.inv ...                                                                                                      
loading intersphinx inventory 'numpy' from https://numpy.org/doc/stable//objects.inv ...                                                                                                       
building [mo]: all of 0 po files
[...]

The culprit is the // before the objects.inv in the URLs. The URL itself is still valid so it's not that critical for Sphinx, but as we compare stdout in our tests, it does not match exactly.

I'll fix the tests to not look a the end of the URL.

[Yannick-Dayer]

It's actually us that give that "malformed" URL to sphinx in the first place.
I found where it was and am fixing it.

No idea why sphinx cleaned the URL before sphinx 8.0 but not after.