Bug#992810: grass: please migrate away from autoconf2.13

[Chris Hofstaedtler]

Source: grass
Version: 7.8.5-2
Tags: upstream

Dear Maintainer,

your package build-depends on autoconf2.13, which is obsolete and
orphaned in Debian.

Please investigate migrating away from autoconf2.13, possibly to
autoconf 2.69 or newer (package name "autoconf").

I see Bas already filed a bug report upstream: https://github.com/OSGeo/grass/issues/560

Best,
Chris