Enable Rubocop Style/StringConcatenation defaults (#23792)

.rubocop_todo.yml

@@ -2263,25 +2263,6 @@ Style/SlicingWithRange:
     - 'lib/mastodon/premailer_webpack_strategy.rb'
     - 'lib/tasks/repo.rake'
 
-# Offense count: 25
-# This cop supports unsafe autocorrection (--autocorrect-all).
-# Configuration parameters: Mode.
-Style/StringConcatenation:
-  Exclude:
-    - 'app/lib/activitypub/case_transform.rb'
-    - 'app/lib/validation_error_formatter.rb'
-    - 'app/services/backup_service.rb'
-    - 'app/services/fetch_link_card_service.rb'
-    - 'lib/mastodon/emoji_cli.rb'
-    - 'lib/mastodon/redis_config.rb'
-    - 'lib/mastodon/snowflake.rb'
-    - 'lib/paperclip/gif_transcoder.rb'
-    - 'lib/paperclip/type_corrector.rb'
-    - 'spec/controllers/api/v1/apps_controller_spec.rb'
-    - 'spec/controllers/api/v1/streaming_controller_spec.rb'
-    - 'spec/validators/disallowed_hashtags_validator_spec.rb'
-    - 'spec/workers/web/push_notification_worker_spec.rb'
-
 # Offense count: 272
 # This cop supports safe autocorrection (--autocorrect).
 # Configuration parameters: EnforcedStyle, MinSize.