... instead of using pkgs/sagemath-standard/setup.py
(which can then be transformed to the modularized build - #34587).
Depends on #32874
Component: build
Work Issues: Cleaner?
Branch/Commit: u/mkoeppe/use_src_setup_py_for_the_installation_mode___disable_editable___disable_wheels @ 8a3b586
Issue created by migration from https://trac.sagemath.org/ticket/34633