$ git clone -n https://src.fedoraproject.org/rpms/os-prober.git /var/lib/mock/f45-build-21178-580/root/chroot_tmpdir/scmroot/os-prober
Cloning into '/var/lib/mock/f45-build-21178-580/root/chroot_tmpdir/scmroot/os-prober'...
$ git fetch origin e02387900d0cc8f3cd704924ebd676480bd1c68b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/os-prober
 * [new ref]         e02387900d0cc8f3cd704924ebd676480bd1c68b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e023879 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild