src/tox.ini: Check that there are no .all imports from namespace packages #32879
Description
We add the following test to the relint linting workflow:
Library code should not import from sage.PAC.KAGE.all when sage.PAC.KAGE is a namespace package (see #32501)
CC: @kwankyu @fchapoton
Component: refactoring
Author: Matthias Koeppe
Branch: 928561e
Reviewer: Kwankyu Lee
Issue created by migration from https://trac.sagemath.org/ticket/32879