Remove pages_update_legacy_storage feature flag

It's superseeded by pages local_store.enabled config flag

Changelog: added

changelogs/unreleased/296138-disable-pages_update_legacy_storage-feature-flag-on-gitlab-com.yml

+---
+title: Remove pages_update_legacy_storage feature flag
+merge_request: 60005
+author:
+type: added

config/feature_flags/development/pages_update_legacy_storage.yml

----
-name: pages_update_legacy_storage
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/50683
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/296138
-milestone: '13.9'
-type: development
-group: group::release
-default_enabled: true

lib/gitlab/pages/settings.rb

@@ -11,10 +11,6 @@ module Gitlab
         super
       end
 
-      def local_store
-        @local_store ||= ::Gitlab::Pages::Stores::LocalStore.new(super)
-      end
-
       private
 
       def disk_access_denied?

lib/gitlab/pages/stores/local_store.rb

-# frozen_string_literal: true
-
-module Gitlab
-  module Pages
-    module Stores
-      class LocalStore < ::SimpleDelegator
-        def enabled
-          return false unless Feature.enabled?(:pages_update_legacy_storage, default_enabled: true)
-
-          super
-        end
-      end
-    end
-  end
-end

spec/lib/gitlab/pages/settings_spec.rb

@@ -47,12 +47,4 @@ RSpec.describe Gitlab::Pages::Settings do
       end
     end
   end
-
-  describe '#local_store' do
-    subject(:local_store) { described_class.new(settings).local_store }
-
-    it 'is an instance of Gitlab::Pages::Stores::LocalStore' do
-      expect(local_store).to be_a(Gitlab::Pages::Stores::LocalStore)
-    end
-  end
 end

spec/lib/gitlab/pages/stores/local_store_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-RSpec.describe Gitlab::Pages::Stores::LocalStore do
-  describe '#enabled' do
-    let(:local_store) { double(enabled: true) }
-
-    subject(:local_store_enabled) { described_class.new(local_store).enabled }
-
-    context 'when the pages_update_legacy_storage FF is disabled' do
-      before do
-        stub_feature_flags(pages_update_legacy_storage: false)
-      end
-
-      it { is_expected.to be_falsey }
-    end
-
-    context 'when the pages_update_legacy_storage FF is enabled' do
-      it 'is equal to the original value' do
-        expect(local_store_enabled).to eq(local_store.enabled)
-      end
-    end
-  end
-end