Alter JupyterLab dockerfile to block target domain / IP from running contiainer

[colelloa]

Hi,

I'd like to be able to alter the sagemaker jupyterlab container to block a certain domain and IP address from being accessed by the jupyterlab user.

I see that aws/studio-lab-examples#118 is not possible, so I cannot use firewalld or iptables, and I cannot seem to get --add-host to work when building the container either. Of course, cannot alter /etc/hosts due to inherent docker functionality there.

Due to our cloud topology, it's unfortunately not possible to do this at the security groups level.