Allow fetch from promisor remote to partially succeed
Problem to solve
It may be that a Git clients objects in want are spread across multiple promisor remotes, and are not available from a single remote. In this situation fetch
will fail because upload-pack
will not be able to fulfill the request because objects are missing.
Proposal
Allow upload-pack
to make a best effort and return some of the objects, even if it does not have all the objects.