functional tests: don't run journal timer
functional tests: don't run journal timer

don't run journal timer for functional tests.
If tearDown/setUp() is called during journal thread is running
by timer, journal thread may be upset by sudden db transaction and
abort.

Change-Id: Ic34a703ac7ceb877175fc299b7e0d7b39ba6db63
Closes-bug: #1700850

openstack/networking-odl,openstack/networking-odl,openstack/networking-odl