$ git clone -n https://src.fedoraproject.org/rpms/rust-mbox.git /var/lib/mock/f45-build-43155-800/root/chroot_tmpdir/scmroot/rust-mbox
Cloning into '/var/lib/mock/f45-build-43155-800/root/chroot_tmpdir/scmroot/rust-mbox'...
$ git fetch origin b216fdd8e594db17684453a32ce708d276394064:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-mbox
 * [new ref]         b216fdd8e594db17684453a32ce708d276394064 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b216fdd Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild