Fix test_apache2.sh test farm test. (#4786)
Fix test_apache2.sh test farm test. (#4786)

tools/venv.sh cannot be used as the tests run on systems with Python 2.6 and
tools/venv.sh installs code that is not compatible with Python 2.6.
jsha/letsencrypt,letsencrypt/letsencrypt,lmcro/letsencrypt,lmcro/letsencrypt,stweil/letsencrypt,stweil/letsencrypt,letsencrypt/letsencrypt,jsha/letsencrypt