Fix newlines in OStatus and RSS serializations (mastodon#10183)

Author: ClearlyClaire

app/lib/formatter.rb

@@ -20,7 +20,7 @@ def format(status, **options)
     raw_content = status.text
 
     if options[:inline_poll_options] && status.poll
-      raw_content = raw_content + '\n\n' + status.poll.options.map { |title| "[ ] #{title}" }.join('\n')
+      raw_content = raw_content + "\n\n" + status.poll.options.map { |title| "[ ] #{title}" }.join("\n")
     end
 
     return '' if raw_content.blank?