poetry env delete and poetry env list should be able to deal with broken envs after a Python upgrade

[ilyagr]

Issue Kind

Change in current behaviour

Description

I ran into #6841, and it is difficult to recover from. I believe the cause of the problem was that the python symlink inside the virtual env pointed to a binary that no longer existed on my system

I wish that:

1. poetry env delete --all worked in that situation. It currently fails with [Errno 2] No such file or directory: 'python'. Ideally, poetry debug info would also work. It currently prints some information, but fails in the same way before printing the useful information of where the virtualenvs are.
2. the error messages suggested I use poetry env delete.

Impact

See above

Workarounds

One can check that poetry config virtualenvs.path is set to a sensible value (DO NOT SKIP THIS PART) and then run rm -r $(poetry config virtualenvs.path)/*.

This is taken from #6841 (comment), which suggested running the above with rm -rf, but judging by the rest of the thread, many people did not check that poetry config virtualenvs.path is set to a reasonable value and nuked large parts of their system. 😬