If this is passed, we add an extra collection id binding to
the commit, as well as create a separate ref for that particular
collection id.
This weakly depends on:
https://github.com/ostreedev/ostree/pull/1805
In that without that change ostree pull will not respect
multiple collection-id bindings. It will still work for
the main/first collection id though.
Closes: #2634
Approved by: alexlarsson
441c1f52ea