Simplify header in custom pages admin index

Now that we're using a component, we can reuse the Header module.

app/components/admin/site_customization/pages/index_component.html.erb

@@ -1,10 +1,7 @@
-<% provide :title do %>
-  <%= t("admin.header.title") %> - <%= t("admin.menu.site_customization.pages") %>
+<%= header do %>
+  <%= link_to t("admin.site_customization.pages.index.create"), new_admin_site_customization_page_path %>
 <% end %>
 
-<%= link_to t("admin.site_customization.pages.index.create"), new_admin_site_customization_page_path, class: "button float-right" %>
-<h2 class="inline-block"><%= t("admin.site_customization.pages.index.title") %></h2>
-
 <% if pages.any? %>
   <h3><%= page_entries_info pages %></h3>
 

app/components/admin/site_customization/pages/index_component.rb

@@ -1,7 +1,14 @@
 class Admin::SiteCustomization::Pages::IndexComponent < ApplicationComponent
+  include Header
   attr_reader :pages
 
   def initialize(pages)
     @pages = pages
   end
+
+  private
+
+    def title
+      t("admin.site_customization.pages.index.title")
+    end
 end