Change container wait logic on system tests
Change container wait logic on system tests

There are 2 system tests which should result in the container still
being running at their end. It's taken me some time, but I think
I've finally isolated the right logic to use when testing these
features.

I'm going to wait 6 seconds after exercising the feature, verifying
that the container is still running after that time. At that point,
I test the output of the logs method to verify that the expected
condition has been met.

Jitsusama/hostel-huptainer