$ git clone -n https://src.fedoraproject.org/rpms/redhat-fonts.git /var/lib/mock/f40-build-2032192-47677/root/chroot_tmpdir/scmroot/redhat-fonts
Cloning into '/var/lib/mock/f40-build-2032192-47677/root/chroot_tmpdir/scmroot/redhat-fonts'...
$ git fetch origin f195f85d6db183c944243645d2f495e7afb651f3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/redhat-fonts
 * [new ref]         f195f85d6db183c944243645d2f495e7afb651f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f195f85 various fixes in spec file