$ git clone -n https://src.fedoraproject.org/rpms/linux-system-roles.git /var/lib/mock/f40-build-2608071-63701/root/chroot_tmpdir/scmroot/linux-system-roles
Cloning into '/var/lib/mock/f40-build-2608071-63701/root/chroot_tmpdir/scmroot/linux-system-roles'...
$ git fetch origin 5e791028d69f0fbfb244f2ffc9f7b9e1dfbe578a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/linux-system-roles
 * [new ref]         5e791028d69f0fbfb244f2ffc9f7b9e1dfbe578a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5e79102 [packit] 1.75.3 upstream release