* ansible-test - prefer venv over virtualenv on Python 3 (#73000)
Also pin virtualenv to 16.7.10 for older Mac OS X systems. This was the version being installed
anway with the previous constraint (<20).
On systems with Python 3, now prefer venv over virtualenv. Test to see if venv is functional since
some systems have a non-functional venv installation (such as Debian).
(cherry picked from commit 850a77f639)
* Make the new ansible-test venv behavior opt-in
Co-authored-by: Sam Doooran <sdoran@redhat.com>
