Log Message:
py-jaraco.envs: updated to 2.4.0

v2.4.0
Made VEnv non-experimental.

v2.3.0
* Added some tests capturing expectations around
  object types for input (use ``path.Path`` object for
  ``root`` property for maximum compatibility).
* Require Python 3.7 or later.
* VirtualEnv classes now expose ``clean_opts`` for easy
  reference in creating clean environments.