Cleanup, pin dind versions
Runner config was fixed, reactivated docker-in-docker job test
As only one single job relies on Docker-in-Docker setup, moved every bit into the job spec.
Aufgrund einer Wartung am 14.05 von 8:00 bis 09:00 Uhr wird das System kurzfristig nicht zur Verfügung stehen. -- Due to maintenance on May the 14th from 8:00 am to 09:00 am the system will temporarily not be available.
Runner config was fixed, reactivated docker-in-docker job test
As only one single job relies on Docker-in-Docker setup, moved every bit into the job spec.