$ git clone -n https://src.fedoraproject.org/rpms/rust-databake.git /var/lib/mock/f42-build-side-115233-61077649-6588695/root/chroot_tmpdir/scmroot/rust-databake
Cloning into '/var/lib/mock/f42-build-side-115233-61077649-6588695/root/chroot_tmpdir/scmroot/rust-databake'...
$ git fetch origin 71385fedfc650fafa1e8a165caadd03863edb292:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-databake
 * [new ref]         71385fedfc650fafa1e8a165caadd03863edb292 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 71385fe Update to version 0.2.0; Fixes RHBZ#2328453