We reinitialize the venv to ensure that the right version of
python is in the venv, but we do not want virtualenv to also
replace pip, setuptools and wheel so we tell it not to. If we
don't do this then virtualenv will install the latest available
version, which is not what we want.
Change-Id: Ic69473a9723df59d0a3a93fb3a8209d59fe1c6b6
Partial-Bug: #1764470