Get rid of srvlookup dependency

[jsf9k]

💡 Summary

We should consider getting rid of the srvlookup dependency.

Motivation and context

On Debian Bookworm, pip now correctly identifies the system Python as being "externally managed" and balks when you try to install pip packages under it. Thus, pip is enforcing the wise rule to only install Python packages under the system python via system packages; if really need to install packages via pip then you should be using a venv.

Unfortunately neither Debian nor RedHat offers a system package for the srvlookup Python package, and it is the only remaining pip package that we are installing. All the other dependencies have been changed to be satisfied via system packages.

[mcdonnnj]

An alternative option is to repackage the verify-cn.py script as a Python package (with an entrypoint) and install it through pipx.