$ git clone -n https://src.fedoraproject.org/rpms/libast.git /var/lib/mock/f45-build-15855-480/root/chroot_tmpdir/scmroot/libast
Cloning into '/var/lib/mock/f45-build-15855-480/root/chroot_tmpdir/scmroot/libast'...
$ git fetch origin 7b11f6ab994fdb0aa9309ae96d905f87c00a9225:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libast
 * [new ref]         7b11f6ab994fdb0aa9309ae96d905f87c00a9225 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7b11f6a Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild