Don't cache only on user

The user itself doesn't update when a new attribute help text or role is
added to them

app/models/attribute_help_text.rb

@@ -30,7 +30,9 @@ class AttributeHelpText < ApplicationRecord
   acts_as_attachable viewable_by_all_users: true
 
   def self.cached(user)
-    OpenProject::Cache.fetch([name, user]) { visible(user).select(:id, :attribute_name).index_by(&:attribute_name) }
+    RequestStore.fetch(name) do
+      visible(user).select(:id, :attribute_name).index_by(&:attribute_name)
+    end
   end
 
   def self.for(model)