Change GET /api/v1/directory to use database replica rather than primary (#26856)

app/controllers/api/v1/directories_controller.rb

@@ -16,8 +16,10 @@ class Api::V1::DirectoriesController < Api::BaseController
   end
 
   def set_accounts
+    with_read_replica do
       @accounts = accounts_scope.offset(params[:offset]).limit(limit_param(DEFAULT_ACCOUNTS_LIMIT))
     end
+  end
 
   def accounts_scope
     Account.discoverable.tap do |scope|