Incorrect entrypoint

Should be ENTRYPOINT ["/home/harbor/start.sh"]

Alternatively it could be the ctl command, but the helm charts are coded to use the arguments of serve /etc/registry/config.yml which doesn't work at all as arguments.

The contents of their start.sh is:

 #!/bin/sh

 set -e

 # The directory /var/lib/registry is within the container, and used to store image in CI testing.
 # So for now we need to chown to it to avoid failure in CI.
 # if [ -d /var/lib/registry ]; then
 #     chown 10000:10000 -R /var/lib/registry
 # fi
 
 /home/harbor/install_cert.sh
 
 /home/harbor/harbor_registryctl -c /etc/registryctl/config.yml

Ignoring the certificate installation (necessary?) then the result is simply to run /home/harbor/harbor_registryctl -c /etc/registryctl/config.yml