[ci] Switching CI to new docker image setup

This MR switches the docker images used by the CI to the new container registry structure here: https://gitlab.cern.ch/cms_tk_ph2/docker_exploration/container_registry/

It also adds the functionality for changes to Dev, tags, and DEBUG modes to trigger a CD job in https://gitlab.cern.ch/cms_tk_ph2/docker_exploration that will build new containers as described in https://gitlab.cern.ch/cms_tk_ph2/docker_exploration/-/issues/2.

The CI job configuration is also significantly simplified.