$ git clone -n https://src.fedoraproject.org/rpms/libical.git /var/lib/mock/f40-build-2242012-53669/root/chroot_tmpdir/scmroot/libical
Cloning into '/var/lib/mock/f40-build-2242012-53669/root/chroot_tmpdir/scmroot/libical'...
$ git fetch origin 0bcda5303aa1b172bcda1f00f5d075708d52d508:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libical
 * [new ref]         0bcda5303aa1b172bcda1f00f5d075708d52d508 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0bcda53 Update to 3.0.17