Part of #32191 (Meta-ticket: Audit/fix all uses of MixedIntegerLinearProgram? in sage.combinat, sage.graphs)

CC: @dcoudert @tscrim @seblabbe @dimpase

Component: linear programming

Author: Matthias Koeppe

Branch/Commit: 20a84da

Reviewer: David Coudert

Issue created by migration from https://trac.sagemath.org/ticket/32220