Switch to the TestItemRunner setup for tests #289
Description
It would be nice to switch to the TestItem setup for tests to have modular tests which can be tested seperately.
At the moment this is blocked by the setup of the testcube because we should avoid to redownload the esdc subset for every testitem separately. Therefore, this would need either a global test setup capability for the @testitemmacro or it would need a way to save the germanycube as an artifact which can then be reused in every testitem separately.