sage.geometry: Use PalpExecutable(...).absolute_filename() #33467
Description
This is so that the Sage library becomes fully functional even when not being run from within sage-env (which sets PATH).
To test:
$ venv/bin/python3 -c 'from sage.all import *; print(lattice_polytope.cross_polytope(3).polar().facets()[0].ambient_point_indices())'
$ venv/bin/python3 -c 'from sage.all import *; from sage.geometry.polyhedron.palp_database import PALPreader; print(next(iter(PALPreader(2, output="list"))))'
Depends on #32893
Depends on #31296
CC: @dimpase
Component: geometry
Author: Matthias Koeppe
Branch/Commit: 4b58ad6
Reviewer: Dima Pasechnik
Issue created by migration from https://trac.sagemath.org/ticket/33467