$ git clone -n https://src.fedoraproject.org/rpms/rust-rocket_cors.git /var/lib/mock/f41-build-side-1-3109836-39404/root/chroot_tmpdir/scmroot/rust-rocket_cors
Cloning into '/var/lib/mock/f41-build-side-1-3109836-39404/root/chroot_tmpdir/scmroot/rust-rocket_cors'...
$ git fetch origin 6867d506dfb91681edf6619ad4e5e98edb96c812:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rocket_cors
 * [new ref]         6867d506dfb91681edf6619ad4e5e98edb96c812 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6867d50 Initial import (fedora#2321515).