Add issues marked for closure to the definition of a milestone's ongoing issues
### Proposal
Issues which are open and unassigned appear in "Unstarted Issues" of a Milestone.
But if they are already referenced via "Closes #XYZ" in a commit which is not yet merged into the master, they should also land in the ongoing issues as the closing command indicates that they are being actively worked on.
Obviously, somebody worked on it and just forgot to assign themselves.
issue