Remove skip test

It has been reported that the bug in docker has now been fixed so we can
re-instate this test.

Signed-off-by: Mazz Mosley <[email protected]>

Author: mnowster

tests/integration_test.py

@@ -380,8 +380,6 @@ def test_invalid_log_driver_raises_exception(self):
 
         assert expected_msg in str(excinfo.value)
 
-    @pytest.mark.skipif(True,
-                        reason="https://github.com/docker/docker/issues/15633")
     def test_valid_no_log_driver_specified(self):
         log_config = docker.utils.LogConfig(
             type="",