Python fixers and linters were failing when vim is running in a virtual
environment that's located in a path containing text `poetry`. The cause
of this was the regular expression `poetry\|pipenv\|uv$` which matches
`poetry` and `pipenv` if they appear anywhere in the virtualenv path.
Add functions to compute the cwd to be the same as the project root for
pylsp and Pyright to work around issues in each language server when
they encounter modules that share the same name as first or third party
libraries.
