Enable more frozen string in app/models/**/*.rb

Partially addresses #47424.

app/models/concerns/storage/legacy_project_wiki.rb

+# frozen_string_literal: true
+
 module Storage
   module LegacyProjectWiki
     extend ActiveSupport::Concern

app/models/concerns/storage/legacy_repository.rb

+# frozen_string_literal: true
+
 module Storage
   module LegacyRepository
     extend ActiveSupport::Concern

app/models/concerns/strip_attribute.rb

+# frozen_string_literal: true
+
 # == Strip Attribute module
 #
 # Contains functionality to clean attributes before validation

app/models/concerns/subscribable.rb

+# frozen_string_literal: true
+
 # == Subscribable concern
 #
 # Users can subscribe to these models.

app/models/concerns/taskable.rb

+# frozen_string_literal: true
+
 require 'task_list'
 require 'task_list/filter'

app/models/concerns/throttled_touch.rb

+# frozen_string_literal: true
+
 # ThrottledTouch can be used to throttle the number of updates triggered by
 # calling "touch" on an ActiveRecord model.
 module ThrottledTouch

app/models/concerns/time_trackable.rb

+# frozen_string_literal: true
+
 # == TimeTrackable concern
 #
 # Contains functionality related to objects that support time tracking.

app/models/concerns/token_authenticatable.rb

+# frozen_string_literal: true
+
 module TokenAuthenticatable
   extend ActiveSupport::Concern

app/models/concerns/triggerable_hooks.rb

+# frozen_string_literal: true
+
 module TriggerableHooks
   AVAILABLE_TRIGGERS = {
     repository_update_hooks:  :repository_update_events,

app/models/concerns/uniquify.rb

+# frozen_string_literal: true
+
 # Uniquify
 #
 # Return a version of the given 'base' string that is unique

app/models/concerns/updated_at_filterable.rb

+# frozen_string_literal: true
+
 module UpdatedAtFilterable
   extend ActiveSupport::Concern

app/models/concerns/valid_attribute.rb

+# frozen_string_literal: true
+
 module ValidAttribute
   extend ActiveSupport::Concern

app/models/concerns/with_uploads.rb

+# frozen_string_literal: true
+
 # Mounted uploaders are destroyed by carrierwave's after_commit
 # hook. This hook fetches upload location (local vs remote) from
 # Upload model. So it's neccessary to make sure that during that

app/models/conversational_development_index/card.rb

+# frozen_string_literal: true
+
 module ConversationalDevelopmentIndex
   class Card
     attr_accessor :metric, :title, :description, :feature, :blog, :docs

app/models/conversational_development_index/idea_to_production_step.rb

+# frozen_string_literal: true
+
 module ConversationalDevelopmentIndex
   class IdeaToProductionStep
     attr_accessor :metric, :title, :features

app/models/conversational_development_index/metric.rb

+# frozen_string_literal: true
+
 module ConversationalDevelopmentIndex
   class Metric < ActiveRecord::Base
     include Presentable

app/models/diff_viewer/added.rb

+# frozen_string_literal: true
+
 module DiffViewer
   class Added < Base
     include Simple

app/models/diff_viewer/base.rb

+# frozen_string_literal: true
+
 module DiffViewer
   class Base
     PARTIAL_PATH_PREFIX = 'projects/diffs/viewers'.freeze

app/models/diff_viewer/client_side.rb

+# frozen_string_literal: true
+
 module DiffViewer
   module ClientSide
     extend ActiveSupport::Concern

app/models/diff_viewer/deleted.rb

+# frozen_string_literal: true
+
 module DiffViewer
   class Deleted < Base
     include Simple