GitLab

* Use "hub" directory for cache instead of "diffusers"

* Import cache locations from huggingface_hub

I verified that the constants are available in huggingface_hub version
0.10.0, which is the minimum we require.
Co-authored-by: Lucain Pouget <lucainp@gmail.com>

* make style

* Move cached directories to new location.

* make style

* Apply suggestions by @Wauplin
Co-authored-by: Lucain <lucainp@gmail.com>

* Fix is_file

* Ignore symlinks.

Especially important if we want to ensure that the user may want to invoke the
process again later, if they are keeping multiple envs with different
versions.

* Style

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Co-authored-by: Lucain Pouget <lucainp@gmail.com>