$ git clone -n https://src.fedoraproject.org/rpms/firecracker.git /var/lib/mock/f41-build-854851-166991/root/chroot_tmpdir/scmroot/firecracker
Cloning into '/var/lib/mock/f41-build-854851-166991/root/chroot_tmpdir/scmroot/firecracker'...
$ git fetch origin 3a06107c737a0d0d565343ca34e6f7446fb0fc3f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/firecracker
 * [new ref]         3a06107c737a0d0d565343ca34e6f7446fb0fc3f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3a06107 Update to version 1.9.0