$ git clone -n https://src.fedoraproject.org/rpms/libidn1.34.git /var/lib/mock/f41-build-886398-16637/root/chroot_tmpdir/scmroot/libidn1.34
Cloning into '/var/lib/mock/f41-build-886398-16637/root/chroot_tmpdir/scmroot/libidn1.34'...
$ git fetch origin b1e2af9c50dcd54e7ea892dc660e6e9a3beb2ba6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libidn1.34
 * [new ref]         b1e2af9c50dcd54e7ea892dc660e6e9a3beb2ba6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b1e2af9 Eliminate use of obsolete %patchN syntax (#2283636)