Add mixin to preserve model_name of CI models

Add a new mixin to CI models which did not extend the now-removed
Gitlab::Ci::Model, so the their `model_name` method is consistent
with the previous behavior.

app/models/ci/freeze_period.rb

@@ -3,6 +3,7 @@
 module Ci
   class FreezePeriod < Ci::ApplicationRecord
     include StripAttribute
+    include Ci::NamespacedModelName
 
     default_scope { order(created_at: :asc) } # rubocop:disable Cop/DefaultScope
 

app/models/ci/pipeline_chat_data.rb

@@ -2,6 +2,8 @@
 
 module Ci
   class PipelineChatData < Ci::ApplicationRecord
+    include Ci::NamespacedModelName
+
     self.table_name = 'ci_pipeline_chat_data'
 
     belongs_to :chat_name

app/models/ci/sources/pipeline.rb

@@ -3,6 +3,8 @@
 module Ci
   module Sources
     class Pipeline < Ci::ApplicationRecord
+      include Ci::NamespacedModelName
+
       self.table_name = "ci_sources_pipelines"
 
       belongs_to :project, class_name: "Project"

app/models/concerns/ci/namespaced_model_name.rb

+# frozen_string_literal: true
+
+module Ci
+  module NamespacedModelName
+    extend ActiveSupport::Concern
+
+    class_methods do
+      def model_name
+        @model_name ||= ActiveModel::Name.new(self, Ci)
+      end
+    end
+  end
+end

ee/app/models/ci/minutes/additional_pack.rb

@@ -8,6 +8,8 @@
 module Ci
   module Minutes
     class AdditionalPack < Ci::ApplicationRecord
+      include Ci::NamespacedModelName
+
       self.table_name = 'ci_minutes_additional_packs'
 
       belongs_to :namespace

ee/app/models/ci/minutes/namespace_monthly_usage.rb

@@ -5,6 +5,8 @@ module Ci
     # Track usage of Shared Runners minutes at root namespace level.
     # This class ensures that we keep 1 record per namespace per month.
     class NamespaceMonthlyUsage < Ci::ApplicationRecord
+      include Ci::NamespacedModelName
+
       belongs_to :namespace
 
       scope :current_month, -> { where(date: beginning_of_month) }

ee/app/models/ci/minutes/project_monthly_usage.rb

@@ -5,6 +5,8 @@ module Ci
     # Track usage of Shared Runners minutes at root project level.
     # This class ensures that we keep 1 record per project per month.
     class ProjectMonthlyUsage < Ci::ApplicationRecord
+      include Ci::NamespacedModelName
+
       belongs_to :project
 
       scope :current_month, -> { where(date: beginning_of_month) }

ee/app/models/ci/sources/project.rb

@@ -3,6 +3,8 @@
 module Ci
   module Sources
     class Project < Ci::ApplicationRecord
+      include Ci::NamespacedModelName
+
       self.table_name = "ci_sources_projects"
 
       belongs_to :pipeline, class_name: "Ci::Pipeline", optional: false

ee/app/models/ci/subscriptions/project.rb

@@ -3,6 +3,7 @@
 module Ci
   module Subscriptions
     class Project < Ci::ApplicationRecord
+      include Ci::NamespacedModelName
       include ::Limitable
 
       self.table_name = 'ci_subscriptions_projects'