Fix Dev branch for next sprint

[LHMoritz]

Describe the bug
The current dev branch does not provide a runnable version of the software.

To Reproduce
Steps to reproduce the behavior:

1. Go to the current dev branch
2. Check out the dev branch and start up the whole software with docker-compose
3. See error: The cluster does not start up reliably and serves all existing functionalities.

Expected behavior
The software starts up reliabliy without errors. The existing funcionalities are usable without errors in one of the modules.

Additional context
The bug blocked the release of sprint 8 therefore it has high priority.