"git repack --geometric" did not work with promisor packs, which
has been corrected.
* ps/geometric-repacking-with-promisor-remotes:
builtin/repack: handle promisor packs with geometric repacking
repack-promisor: extract function to remove redundant packs
repack-promisor: extract function to finalize repacking
repack-geometry: extract function to compute repacking split
builtin/pack-objects: exclude promisor objects with "--stdin-packs"