Change virtual environments to be reused if the virtual environment is
already set up with the same frozen requirements. The only venv not
reused by default is the wheel testing venv because it installs the
package and so it is a bit trickier to do intelligently.
Change virtual environments to be reused if the virtual environment is already set up with the same frozen requirements. The only venv not reused by default is the wheel testing venv because it installs the package and so it is a bit trickier to do intelligently.