Set OS_TEST_LOCK_PATH default value in fake_config

This commit sets OS_TEST_LOCK_PATH default value in fake_config.
Originally, a 'None' directory was created after a unit test running.
Because we don't specified the environment variable when we run unit
tests. Let's stop making a weird 'None' directory.

Change-Id: I850f0835af821e90d85a9366d0ef87618761216a
1 file changed