Lazy load CondaPkg (and Pkg), I think LazyModules for that, or better option?

At least when I set:
ENV["JULIA_CONDAPKG_BACKEND"] = "Null"

I get: ERROR: InitError: CondaPkg is using the Null backend but Python is not installed

though, so not investigating further (I have Python installed).

With this one loads but not any faster (but should too):
```
ENV["JULIA_PYTHONCALL_EXE"] = "@PyCall" # optional

julia> ENV["JULIA_PYTHONCALL_EXE"] ="/usr/local/bin/python3";

julia> @time using PythonCall
┌ Warning: Python library "/usr/local/lib/python3.12/config-3.12-x86_64-linux-gnu/libpython3.12.a" could not be opened.
└ @ PythonCall.C ~/.julia/dev/PythonCall/src/C/context.jl:122
┌ Warning: Python library "/usr/local/lib/libpython3.12.a" could not be opened.
└ @ PythonCall.C ~/.julia/dev/PythonCall/src/C/context.jl:122
ERROR: InitError: Could not find Python library for Python executable "/usr/local/bin/python3".

If you know where the library is, set environment variable 'JULIA_PYTHONCALL_LIB' to its path.
```