Apply Layout/LineLength rubocop rule

Note we're excluding a few files:

* Configuration files that weren't generated by us
* Migration files that weren't generated by us
* The Gemfile, since it includes an important comment that must be on
  the same line as the gem declaration
* The Budget::Stats class, since the heading statistics are a mess and
  having shorter lines would require a lot of refactoring

app/helpers/admin_helper.rb

@@ -6,7 +6,10 @@ module AdminHelper
   def official_level_options
     options = [["", 0]]
     (1..5).each do |i|
-      options << [[t("admin.officials.level_#{i}"), setting["official_level_#{i}_name"]].compact.join(": "), i]
+      options << [
+        [t("admin.officials.level_#{i}"), setting["official_level_#{i}_name"]].compact.join(": "),
+        i
+      ]
     end
     options
   end