RFE: have elpy install setuptools into the rpc-venv for newer Pythons

[space88man]

Summary

Newer versions of Python don't have distutils and with the package set that elpy installs nothiing provides pkg_resources (used by blackutil.py and jedibackend.py).

The virtualenv needs to have setuptools installed.

Steps to reproduce

Install elpy under Python 3.12 and let it create rpc-venv.

My configuration

OS

Fedora 39beta, Python 3.12, elpy-20230803.1455 (user installation from melpa)

Result of (elpy-config)

With out pkg_resources elpy can't detect any packages at all. Elpy and the virtualenv packages are all shown as None

Elpy configuration in my init.el

(use-package elpy
  :ensure t
  :init
  (elpy-enable))

Workaround: manually install setuptools into rpc-venv OR create a separate virtualenv with all the requirements installed and set '(elpy-rpc-virtualenv-path 'current).