Use abstract_method for Polyhedra

[kliem]

This is simpler and has the advantage that the TestSuite checks that objects do not have a (non-optional) not implemented abstract method.

CC: @mkoeppe

Component: geometry

Author: Jonathan Kliem

Branch/Commit: 5d0cbf8

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/33679

[kliem]

Branch: public/33679

[kliem]

Commit: 5d0cbf8

[kliem]

New commits:

5d0cbf8

use abstract_method for Polyhedra

[mkoeppe]

Reviewer: Matthias Koeppe

[vbraun]

Changed branch from public/33679 to 5d0cbf8