On Tue, 2021-03-16 at 09:08 +0100, Léo Le Bouter via Bug reports for
GNU Guix wrote:
> There is no new upstream release so patching this appears to be some
> kind of sport.

There seems to be a release candidate available: 
https://lists.gnu.org/archive/html/grub-devel/2021-03/msg00219.html