Modify the '.gitignore' file
Modify the '.gitignore' file

Since the horizon remove the 'run_tests.sh' file,
so there should remove '.venv' from the '.gitignore' file.
See the patch 'https://review.openstack.org/#/c/399842/'

Change-Id: Id0dc24907b7b5fc0191cfc6a58b902ee313a8b55

stackforge/senlin-dashboard,openstack/senlin-dashboard,stackforge/senlin-dashboard,openstack/senlin-dashboard,openstack/senlin-dashboard,openstack/senlin-dashboard,stackforge/senlin-dashboard