$ git clone -n https://src.fedoraproject.org/rpms/rust-md5.git /var/lib/mock/f45-build-43162-800/root/chroot_tmpdir/scmroot/rust-md5
Cloning into '/var/lib/mock/f45-build-43162-800/root/chroot_tmpdir/scmroot/rust-md5'...
$ git fetch origin 7efbaf5220d49bc8bddee13f44fdb5fc14e70851:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-md5
 * [new ref]         7efbaf5220d49bc8bddee13f44fdb5fc14e70851 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7efbaf5 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild