Updated openstack/openstack
Project: openstack/keystone  3ec0c5e693e15754bca2dbebeaacac223272ad68

Fixed the policy tests in Python 3

The file builtin was removed in Python 3. open should be used instead.

bp python3

Change-Id: Ib394b9ceeffb1ae8fd4cbebbd0818c64e24e55e6