The integration tests depend on the presence of external servers
and the user settings.
First, people are bothered by failing test due to problems with
those servers and second, administrators need to run phpunit tests
to verify the configuration settings.
Therefore, we move the integration tests to a special page.
Bug: T87389
Change-Id: If66f13fe7fa16868cd4b1d8f0e0a6e3d49448b27
physikerwelt (Moritz Schubotz)