Remove motd spam after installing fake ubuntu advantage tools

lib/functions/compilation/packages/fake_ubuntu_advantage_tools-deb.sh

@@ -36,6 +36,14 @@ function compile_fake_ubuntu_advantage_tools() {
 		Description: Ban ubuntu-advantage-tools while satisfying ubuntu-minimal dependency
 	END
 
+	# set up post install script
+	cat <<- END > DEBIAN/postinst
+		#!/bin/sh
+		rm -f /var/lib/ubuntu-advantage/messages/motd-esm-announce 2> /dev/null
+		exit 0
+	END
+
+
 	cd "${fw_temp_dir}" || exit_with_error "can't change directory"
 
 	# package, directly to DEB_STORAGE; full version might be very big for tmpfs.