Enable Rubocop Style/FrozenStringLiteralComment (#23793)

app/views/accounts/show.rss.ruby

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSS::Builder.build do |doc|
   doc.title(display_name(@account))
   doc.description(I18n.t('rss.descriptions.account', acct: @account.local_username_and_domain))

app/views/tags/show.rss.ruby

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSS::Builder.build do |doc|
   doc.title("##{@tag.display_name}")
   doc.description(I18n.t('rss.descriptions.tag', hashtag: @tag.display_name))

app/views/well_known/host_meta/show.xml.ruby

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 doc = Ox::Document.new(version: '1.0')
 
 doc << Ox::Element.new('XRD').tap do |xrd|