DOC: Generating docs doesn't work if path has whitespaces
Related to #20862

If there are spaces in the path where pandas is installed (e.g. `/home/my user/my code/pandas`), when building the documentation (i.e. `./doc/make.py html`) seems to generate a long list of usage errors like those:

```
UsageError: %bookmark: too many arguments
UsageError: %bookmark -d: Can't delete bookmark 'ipy_savedir'
```