Merge branch 'limit-spec-job-to-branches' into 'master'

Set default value for `PRIVATE_TOKEN` environment variable

See merge request gitlab-com/www-gitlab-com!23159

lib/changelog.rb

@@ -9,7 +9,7 @@ require_relative 'changelog/rss'
 Gitlab.configure do |config|
   config.endpoint = 'https://gitlab.com/api/v4'
-  config.private_token = ENV.fetch('PRIVATE_TOKEN')
+  config.private_token = ENV.fetch('PRIVATE_TOKEN', nil)
 end
 module Changelog