Optimize the number of auth requests

[Wwwsylvia]

We had an issue on ORAS for optimizing the number of auth request: oras-project/oras#1097
We should also review oras-go and apply similar optimization. For instance, we can add pull scope hint in addition to delete in the referrers tag schema code path on manifest delete:

oras-go/registry/remote/repository.go

Lines 1116 to 1125 in 577bffe

	manifestJSON, err := content.FetchAll(ctx, s, target)
	if err != nil {
	return err
	}
	if err := s.indexReferrersForDelete(ctx, target, manifestJSON); err != nil {
	return err
	}
	}
	return s.repo.delete(ctx, target, true)