Checkmk Werk 14801: Improve detection when OMD runs in a container

ID: 14801 Title: Improve detection when OMD runs in a container Component: Site Management Level: 1 Class: Bug fix Version: 2.2.0i1 Only for docker and podman we could reliably detect if OMD is running in a container. The official docker image now sets a CMK_CONTAINERIZED=TRUE environment variable that is checked in omd. This works independent of the container runtime used.