$ git clone -n https://src.fedoraproject.org/rpms/linux-system-roles.git /var/lib/mock/f40-build-2265098-54583/root/chroot_tmpdir/scmroot/linux-system-roles
Cloning into '/var/lib/mock/f40-build-2265098-54583/root/chroot_tmpdir/scmroot/linux-system-roles'...
$ git fetch origin a27345d5392a6625b72f1292de6b60b7d880c4a8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/linux-system-roles
 * [new ref]         a27345d5392a6625b72f1292de6b60b7d880c4a8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a27345d Add ExcludeArch i686 to fix build issues with ansible-core