Bump copyright year to 2024 (#197)

Wow, this sounds like the ten years of DuniterPy. Time flies.

commit 63962d750c974cf1d1c3d435691f18a7cb8f06b8
Author: Caner Candan <caner@candan.fr>
Date:   Tue Jan 14 06:04:05 2014 -0800

    Initial commit

Close #197 (closed).

changed milestone to %1.2.0

assigned to @moul

changed the description

requested review from @vtexier

approved this merge request

merged