$ git clone -n https://src.fedoraproject.org/rpms/libidn.git /var/lib/mock/f41-build-1266645-23069/root/chroot_tmpdir/scmroot/libidn
Cloning into '/var/lib/mock/f41-build-1266645-23069/root/chroot_tmpdir/scmroot/libidn'...
$ git fetch origin cbe1eaae7717c4b871080fa378ddb9b05343302f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libidn
 * [new ref]         cbe1eaae7717c4b871080fa378ddb9b05343302f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cbe1eaa Eliminate use of obsolete %patchN syntax (#2283636)