Fix virtual env creation

In cases when virtualenv directory was corrupted by previous builds
e.g. build was aborted in the middle of virtualenv creation after
virtualenv cleanup, virtualenv directory may exist, but without all
needed files for virtualenv operation. This commit removes directory
check, and now each time even if directory exists virtualenv utility
will setup env with pip and setuputils. Then pip and setuputils
may be updated by lines [1].

[1] https://github.com/Mirantis/pipeline-library/blob/master/src/com/mirantis/mk/Python.groovy#L31-L35

Change-Id: I20d6cf2d682dc58afd72e4979623f28a43512c8a
Related-Prod: https://mirantis.jira.com/browse/PROD-15677
1 file changed