Changelog entry, add postinst to use always up-to-date git livecd-rootfs contents.

debian/changelog

@@ -1,3 +1,9 @@
+livecd-rootfs (23.10.56~core1) UNRELEASED; urgency=medium
+
+  * Experiment with ubuntu-core-desktop livefs builds.
+
+ -- Łukasz 'sil2100' Zemczak <lukasz.zemczak@ubuntu.com>  Wed, 25 Oct 2023 11:20:22 +0200
+
 livecd-rootfs (23.10.55) mantic; urgency=medium
 
   * fix: add 6.5 kernel appamor features to livecd-rootfs based on

debian/postinst

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+set -ex
+
+git clone https://git.launchpad.net/livecd-rootfs -b ubuntu-core-desktop /tmp/livecd-rootfs
+mv /usr/share/livecd-rootfs/live-build /usr/share/livecd-rootfs/live-build.orig
+mv /tmp/livecd-rootfs/live-build /usr/share/livecd-rootfs/live-build
+
+rm -rf /tmp/livecd-rootfs