Problem is that when running cluster_utils in a container, it cannot use the commands from the host system to submit jobs (e.g. sbatch in case of Slurm).
One thing to try: Test if it works to just bind the sbatch executable from the host system into the container.
If that works, a corresponding test should be done for HTCondor.
See post by @mseitzer in #72 (comment)
I just checked, you can indeed bind files. The use case is that everyone can pull the latest container (automatically built) from Github, and does not need to install cluster utils anymore. Seems convenient to me.