Test session brakeman fix

Author: arkirchner

app/controllers/test_sessions_controller.rb

@@ -8,7 +8,12 @@ class TestSessionsController < ApplicationController
   def create
     raise 'test authorisation called outside of test environment' unless Rails.env.test?
 
-    user = params[:user_class].constantize.find(params[:user_id])
+    user = if params[:user_class] == 'ExternalUser'
+             ExternalUser.find(params[:user_id])
+           else
+             InternalUser.find(params[:user_id])
+           end
+
     auto_login(user)
     head :ok
   end