$ git clone -n https://src.fedoraproject.org/rpms/libnxt.git /var/lib/mock/f41-build-825681-154652/root/chroot_tmpdir/scmroot/libnxt
Cloning into '/var/lib/mock/f41-build-825681-154652/root/chroot_tmpdir/scmroot/libnxt'...
$ git fetch origin 0001e02a57e71e1980bd264526c215fc59762d3a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libnxt
 * [new ref]         0001e02a57e71e1980bd264526c215fc59762d3a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0001e02 ExcludeArch ix86 (fixes FTBFS, rhbz#2300908)