Remove scaffolding from controller

- landing page content items are now fully available from
  content store (in practise) and publishing-api schemas
  (during tests), so this scaffolding is now no longer necessary.
- we no longer need to skip the before action.

app/controllers/landing_page_controller.rb

@@ -1,44 +1,3 @@
 class LandingPageController < ContentItemsController
   slimmer_template "gem_layout_full_width"
-  skip_before_action :set_content_item_and_cache_control
-
-private
-
-  # SCAFFOLDING: can be removed when basic content items are available
-  # from content-store
-  def content_item
-    @content_item ||= ContentItemFactory.build(old_scaffolding_content_item)
-  end
-
-  # SCAFFOLDING: can be removed when basic content items are available
-  # from content-store
-  def old_scaffolding_content_item
-    result = ContentItemLoader.for_request(request).load(request.path)
-    return result.to_h if result.is_a?(GdsApi::Response)
-
-    fake_data
-  end
-
-  # SCAFFOLDING: can be removed when basic content items are available
-  # from content-store
-  def fake_data
-    {
-      "base_path" => request.path,
-      "title" => "Landing Page",
-      "description" => "A landing page example",
-      "locale" => "en",
-      "document_type" => "landing_page",
-      "schema_name" => "landing_page",
-      "publishing_app" => "whitehall",
-      "rendering_app" => "frontend",
-      "update_type" => "major",
-      "details" => {},
-      "routes" => [
-        {
-          "type" => "exact",
-          "path" => request.path,
-        },
-      ],
-    }
-  end
 end