libidn2: update to 2.3.1.

By ericonr:
- add changelog

Closes: void-linux#31182 [via git-merge-pr]

srcpkgs/libidn2/template

@@ -1,6 +1,6 @@
 # Template file for 'libidn2'
 pkgname=libidn2
-version=2.3.0
+version=2.3.1
 revision=1
 build_style=gnu-configure
 hostmakedepends="automake gettext-devel libtool pkg-config"
@@ -9,8 +9,9 @@ short_desc="Internationalized string handling library"
 maintainer="Enno Boland <gottox@voidlinux.org>"
 license="GPL-3.0-or-later, LGPL-3.0-or-later"
 homepage="https://www.gnu.org/software/libidn/#libidn2"
+changelog="https://gitlab.com/libidn/libidn2/-/raw/master/NEWS"
 distfiles="${GNU_SITE}/libidn/libidn2-${version}.tar.gz"
-checksum=e1cb1db3d2e249a6a3eb6f0946777c2e892d5c5dc7bd91c74394fc3a01cab8b5
+checksum=8af684943836b8b53965d5f5b6714ef13c26c91eaa36ce7d242e3d21f5d40f2d
 
 pre_configure() {
 	autoreconf -if