$ git clone -n https://src.fedoraproject.org/rpms/libserf.git /var/lib/mock/f38-build-side-42-init-devel-740602-27656/root/chroot_tmpdir/scmroot/libserf
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-740602-27656/root/chroot_tmpdir/scmroot/libserf'...
$ git fetch origin 84813ce0070bed80de4d7fd07c2da91e7ce80525:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libserf
 * [new ref]         84813ce0070bed80de4d7fd07c2da91e7ce80525 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 84813ce Do not test on i686