This is implementing #24024 for the flint and arb packages which use basically the same "build system".

This shouldn't change much anything in the end result of installing these packages, but I bumped the version numbers just to ensure testing on the buildbots.

Depends on #23733

Component: build

Keywords: destdir flint arb

Author: Erik Bray

Branch/Commit: a9971d7

Reviewer: Frédéric Chapoton

Issue created by migration from https://trac.sagemath.org/ticket/25035