fixes for failed cron maintenance tasks

* update rails scripts for 5.2
* system dmails should be scoped to system
* fix broken url generator in forum notices

config/spring.rb

@@ -1,6 +1,6 @@
-%w(
+%w[
   .ruby-version
   .rbenv-vars
   tmp/restart.txt
   tmp/caching-dev.txt
-).each { |path| Spring.watch(path) }
+].each { |path| Spring.watch(path) }