$ git clone -n https://src.fedoraproject.org/rpms/cantera.git /var/lib/mock/f39-build-1931228-43111/root/chroot_tmpdir/scmroot/cantera
Cloning into '/var/lib/mock/f39-build-1931228-43111/root/chroot_tmpdir/scmroot/cantera'...
$ git fetch origin 162292f4b06419489fe18a0edf676ea9b6228fb7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cantera
 * [new ref]         162292f4b06419489fe18a0edf676ea9b6228fb7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 162292f update to v3.0.0