$ git clone -n https://src.fedoraproject.org/rpms/fbreader.git /var/lib/mock/f45-build-8723-394/root/chroot_tmpdir/scmroot/fbreader
Cloning into '/var/lib/mock/f45-build-8723-394/root/chroot_tmpdir/scmroot/fbreader'...
$ git fetch origin cc46eaaa9230bc71c1d052aa8362264f930f0ccd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/fbreader
 * [new ref]         cc46eaaa9230bc71c1d052aa8362264f930f0ccd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cc46eaa Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild