$ git clone -n https://src.fedoraproject.org/rpms/rust-stacker.git /var/lib/mock/f45-build-45160-821/root/chroot_tmpdir/scmroot/rust-stacker
Cloning into '/var/lib/mock/f45-build-45160-821/root/chroot_tmpdir/scmroot/rust-stacker'...
$ git fetch origin 2c16326410a20da17ca3194e939aa09875f652d5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-stacker
 * [new ref]         2c16326410a20da17ca3194e939aa09875f652d5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2c16326 Update to version 0.1.25; Fixes RHBZ#2437476