Add finalize to NullSession so it quacks like a Session

Author: leequarella

activerecord/lib/active_record/asynchronous_queries_tracker.rb

@@ -7,6 +7,9 @@ class << self
         def active?
           true
         end
+
+        def finalize
+        end
       end
     end
 
@@ -50,7 +53,7 @@ def start_session
     end
 
     def finalize_session
-      @current_session.finalize if @current_session.respond_to?(:finalize)
+      @current_session.finalize
       @current_session = NullSession
     end
   end