Improve ConnectionHandlingTest

As pointed by Carlos on the PR.

Author: byroot

activerecord/test/cases/connection_handling_test.rb

@@ -39,8 +39,8 @@ class ConnectionHandlingTest < ActiveRecord::TestCase
           assert_same ActiveRecord::Base.connection, connection
 
           ActiveRecord::Base.with_connection do |connection2|
-            assert_same leased_connection, connection
-            assert_same ActiveRecord::Base.connection, connection
+            assert_same leased_connection, connection2
+            assert_same ActiveRecord::Base.connection, connection2
           end
         end