Fix add model like

[LysandreJik]

It seems that pip show does not return the same location as before for editable packages.

However, listing editable packages (pip list -e) returns the correct location in which it was installed. Doing it locally returns the following:

Package      Version     Editable project location
------------ ----------- ---------------------------------------------
transformers 4.22.0.dev0 /home/lysandre/Workspaces/python/transformers

I'm therefore updating the way to identify if we're looking at the correct install to use pip list -e instead of pip show.

[sgugger]

Thanks for fixing!

[HuggingFaceDocBuilderDev]

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