$ git clone -n https://src.fedoraproject.org/rpms/rust-maplit.git /var/lib/mock/f45-build-43121-800/root/chroot_tmpdir/scmroot/rust-maplit
Cloning into '/var/lib/mock/f45-build-43121-800/root/chroot_tmpdir/scmroot/rust-maplit'...
$ git fetch origin 87df5bd82382bfec1860c9667a3921f0b5da27f7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-maplit
 * [new ref]         87df5bd82382bfec1860c9667a3921f0b5da27f7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 87df5bd Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild