Fix finish script for s6 v3 (#75)

* Fix finish script for s6 v3

* Empty line at end

rootfs/etc/services.d/mdns/finish

@@ -1,8 +1,15 @@
-#!/usr/bin/execlineb -S0
+#!/usr/bin/env bashio
 # ==============================================================================
 # Take down the S6 supervision tree when mDNS repeater fails
+# s6-overlay docs: https://github.com/just-containers/s6-overlay
 # ==============================================================================
-if { s6-test ${1} -ne 0 }
-if { s6-test ${1} -ne 256 }
+declare APP_EXIT_CODE=${1}
+
+if [[ "${APP_EXIT_CODE}" -ne 0 ]] && [[ "${APP_EXIT_CODE}" -ne 256 ]]; then
+  bashio::log.warning "Halt mDNS plug-in with exit code ${APP_EXIT_CODE}"
+  echo "${APP_EXIT_CODE}" > /run/s6-linux-init-container-results/exitcode
+  exec /run/s6/basedir/bin/halt
+fi
+
+bashio::log.info "Service restart after closing"
 
-s6-svscanctl -t /var/run/s6/services