$ git clone -n https://src.fedoraproject.org/rpms/libwnck3.git /var/lib/mock/f45-build-17259-497/root/chroot_tmpdir/scmroot/libwnck3
Cloning into '/var/lib/mock/f45-build-17259-497/root/chroot_tmpdir/scmroot/libwnck3'...
$ git fetch origin 9adf21972dfe1f6a1a443202a25d452e5d5dd0b2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libwnck3
 * [new ref]         9adf21972dfe1f6a1a443202a25d452e5d5dd0b2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9adf219 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild