$ git clone -n https://src.fedoraproject.org/rpms/plasma-workspace-wallpapers.git /var/lib/mock/f45-build-28844-633/root/chroot_tmpdir/scmroot/plasma-workspace-wallpapers
Cloning into '/var/lib/mock/f45-build-28844-633/root/chroot_tmpdir/scmroot/plasma-workspace-wallpapers'...
$ git fetch origin 12802a9985961928f901e68955bfe33e21375920:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-workspace-wallpapers
 * [new ref]         12802a9985961928f901e68955bfe33e21375920 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 12802a9 6.7.5