$ git clone -n https://src.fedoraproject.org/rpms/facter.git /var/lib/mock/f38-build-side-42-init-devel-664631-26644/root/chroot_tmpdir/scmroot/facter
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-664631-26644/root/chroot_tmpdir/scmroot/facter'...
$ git fetch origin e962ce921cc91cd9809ddda5479da2a4a58b8d7d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/facter
 * [new ref]         e962ce921cc91cd9809ddda5479da2a4a58b8d7d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e962ce9 Add BR: rubygem-sys-filesystem