feat: Use deb822 APT source for armbian-config

- Replace creation of `armbian-config.list` with
  `armbian-config.sources`. This holds the same information in a newer
  format, deb822. This does not affect `armbian.list`.

See also: armbian/configng#407

extensions/armbian-config.sh

@@ -2,8 +2,14 @@
 # and they are moved to main armbian repo periodically
 
 
-function custom_apt_repo__add_armbian-github-repo(){
-	echo "deb ${SIGNED_BY}https://github.armbian.com/configng stable main" > "${SDCARD}"/etc/apt/sources.list.d/armbian-config.list
+function custom_apt_repo__add_armbian-github-repo() {
+	cat <<- EOF > "${SDCARD}"/etc/apt/sources.list.d/armbian-config.sources
+	Types: deb
+	URIs: https://github.armbian.com/configng
+	Suites: stable
+	Components: main
+	Signed-By: "${APT_SIGNING_KEY_FILE}"
+	EOF
 }
 
 

lib/functions/rootfs/distro-specific.sh

@@ -160,8 +160,9 @@ function create_sources_list_and_deploy_repo_key() {
 	display_alert "Adding Armbian repository and authentication key" "${when} :: /etc/apt/sources.list.d/armbian.list" "info"
 	mkdir -p "${basedir}"/usr/share/keyrings
 	# change to binary form
-	gpg --dearmor < "${SRC}"/config/armbian.key > "${basedir}"/usr/share/keyrings/armbian.gpg
-	SIGNED_BY="[signed-by=/usr/share/keyrings/armbian.gpg] "
+	APT_SIGNING_KEY_FILE="/usr/share/keyrings/armbian.gpg"
+	gpg --dearmor < "${SRC}"/config/armbian.key > "${basedir}${APT_SIGNING_KEY_FILE}"
+	SIGNED_BY="[signed-by=${APT_SIGNING_KEY_FILE}] "
 
 	# lets keep old way for old distributions
 	if [[ "${RELEASE}" =~ (focal|bullseye) ]]; then