Remove dependency on db during assets:precompile (#5138)

app/views/layouts/error.html.haml

@@ -3,7 +3,7 @@
   %head
     %meta{ content: 'text/html; charset=UTF-8', 'http-equiv' => 'Content-Type' }/
     %meta{ charset: 'utf-8' }/
-    %title= safe_join([yield(:page_title), title], ' - ')
+    %title= safe_join([yield(:page_title), Setting.default_settings['site_title']], ' - ')
     %meta{ content: 'width=device-width,initial-scale=1', name: 'viewport' }/
     = stylesheet_pack_tag 'common', media: 'all'
     = stylesheet_pack_tag Setting.default_settings['theme'], media: 'all'