`nbdev_docs` raises `FileNotFoundError` when looking for `_proc/docs`

Hi, I am having some recent trouble creating the docs for my library (https://github.com/andichallenge/andi_datasets). Everything used to work fine but recently, whenever I try to run `nbdev_docs`, I get this error:

```
FileNotFoundError: [Errno 2] No such file or directory: '/home/gorka/github/andi_datasets/_proc/docs' -> '/home/gorka/github/andi_datasets/docs'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/home/gorka/miniconda3/envs/andi/bin/nbdev_docs", line 8, in
sys.exit(nbdev_docs())
File "/home/gorka/miniconda3/envs/andi/lib/python3.10/site-packages/fastcore/script.py", line 119, in _f
return tfunc(**merge(args, args_from_prog(func, xtra)))
File "/home/gorka/miniconda3/envs/andi/lib/python3.10/site-packages/nbdev/quarto.py", line 230, in nbdev_docs
move(cache/cfg.doc_path.name, cfg.config_path)
File "/home/gorka/miniconda3/envs/andi/lib/python3.10/site-packages/fastcore/shutil.py", line 8, in _f
def _f(src, dst, *args, **kwargs): return f(str(src), str(dst), *args, **kwargs)
File "/home/gorka/miniconda3/envs/andi/lib/python3.10/shutil.py", line 835, in move
copy_function(src, real_dst)
File "/home/gorka/miniconda3/envs/andi/lib/python3.10/shutil.py", line 434, in copy2
copyfile(src, dst, follow_symlinks=follow_symlinks)
File "/home/gorka/miniconda3/envs/andi/lib/python3.10/shutil.py", line 254, in copyfile
with open(src, 'rb') as fsrc:
FileNotFoundError: [Errno 2] No such file or directory: '/home/gorka/github/andi_datasets/_proc/docs'
```

Somehow `nbdev_docs`, is looking for `_proc/docs`, which does not exists. `nbdev_preview` works just fine and I can see the docs in my localhost. I have run `nbdev_docs` in another similar library and everything works fine there, even though `_proc/docs` is neither being created in that one.

How is it that in this library `nbdev_docs` looks for `_proc/docs`? Nothing in the settings.ini or so seems to point there. This means that also the CI is failing when pushing to github. Any leads on how to solve this? Thanks!

Beginnen Sie bei nbdev/quarto.py, ungefähr bei nbdev_docs, Zeile 230, und untersuchen Sie, wie cfg.doc_path und cfg.config_path abgeleitet werden. Vergleichen Sie anschließend das Verhalten mit nbdev_preview und der betroffenen settings.ini. Reproduzieren Sie den Befehl in der gemeldeten Bibliothek und verifizieren Sie, dass nbdev_docs abgeschlossen wird, ohne einen nicht existierenden _proc/docs-Pfad zu benötigen, und dass CI nicht mehr fehlschlägt.

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