Autofix Rubocop Style/PerlBackrefs (#23649)

.rubocop_todo.yml

@@ -3087,12 +3087,6 @@ Style/OptionalBooleanParameter:
     - 'app/workers/unfollow_follow_worker.rb'
     - 'lib/mastodon/redis_config.rb'
 
-# Offense count: 2
-# This cop supports safe autocorrection (--autocorrect).
-Style/PerlBackrefs:
-  Exclude:
-    - 'app/lib/extractor.rb'
-
 # Offense count: 1
 # This cop supports unsafe autocorrection (--autocorrect-all).
 # Configuration parameters: EnforcedStyle.

app/lib/extractor.rb

@@ -29,7 +29,7 @@ module Extractor
 
     text.scan(Account::MENTION_RE) do |screen_name, _|
       match_data = $LAST_MATCH_INFO
-      after      = $'
+      after      = ::Regexp.last_match.post_match
 
       unless Twitter::TwitterText::Regex[:end_mention_match].match?(after)
         _, domain = screen_name.split('@')
@@ -64,7 +64,7 @@ module Extractor
       match_data     = $LAST_MATCH_INFO
       start_position = match_data.char_begin(1) - 1
       end_position   = match_data.char_end(1)
-      after          = $'
+      after          = ::Regexp.last_match.post_match
 
       if %r{\A://}.match?(after)
         hash_text.match(/(.+)(https?\Z)/) do |matched|