can enroot overwrite entrypoint of docker image just like how docker run works. #266

as we know, official vllm docker image's entrypoint is 'vllm serve',
and in docker environment we can use --entrypoint option to overwrite the default entrypoint like this:
docker run --entrypoint /bin/bash vllm/vllm-openai:v0.18.0

when I use same image in enroot environment, seems this is no way to overwrite it.
enroot create --name vllm-testagent vllm-openai-v0.18.0.sqsh
enroot start --root --rw vllm-testagent bash -c "echo hello"

a workaround is build another image use docker file like:
FROM vllm/vllm-openai:v0.18.0
ENTRYPOINT []
CMD ["/bin/bash"]
WORKDIR /root

is that possible to overwrite default entrypoint in enroot environment? thanks.