$ git clone -n https://src.fedoraproject.org/rpms/libfm.git /var/lib/mock/f45-build-16177-483/root/chroot_tmpdir/scmroot/libfm
Cloning into '/var/lib/mock/f45-build-16177-483/root/chroot_tmpdir/scmroot/libfm'...
$ git fetch origin 39b39cf7e15e75c79c44edfb41d73f1d3739c600:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libfm
 * [new ref]         39b39cf7e15e75c79c44edfb41d73f1d3739c600 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 39b39cf Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild