Correctly disable greendns
Correctly disable greendns

Previously, we were setting the environment variable to disable
greendns in eventlet *after* import eventlet. This has no effect, as
eventlet processes environment variables at import time. This patch
moves the setting of EVENTLET_NO_GREENDNS before importing eventlet in
order to correctly disable greendns.

Closes-bug: 1895322
Change-Id: I4deed815c8984df095019a7f61d089f233f1fc66

klmitch/nova,mahak/nova,mahak/nova,mahak/nova,klmitch/nova,klmitch/nova,openstack/nova,klmitch/nova,openstack/nova,openstack/nova