$ git clone -n https://src.fedoraproject.org/rpms/udunits2.git /var/lib/mock/f41-build-1042166-18998/root/chroot_tmpdir/scmroot/udunits2
Cloning into '/var/lib/mock/f41-build-1042166-18998/root/chroot_tmpdir/scmroot/udunits2'...
$ git fetch origin ad47809037669cf7a3efba483af0b2ce736f65f5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/udunits2
 * [new ref]         ad47809037669cf7a3efba483af0b2ce736f65f5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ad47809 Eliminate use of obsolete %patchN syntax (#2283636)