[Note: against F22-branch, but installing rawhide content, that's how I hit the bug]
systemd changed to generate a symlink resolv.conf -> /run/networkd/resolv.conf which doesn't exist at installation time.
(What we should do at some point is tell NetworkManager to serialize its state into the installation root and get out of the business of writing these files directly)
https://bugzilla.redhat.com/show_bug.cgi?id=1116651