[Security] fixed typo in a test

Author: fabpot

src/Symfony/Component/Security/Tests/Http/EntryPoint/FormAuthenticationEntryPointTest.php

@@ -64,7 +64,7 @@ public function testStartWithUseForward()
  $httpKernel
  ->expects($this->once())
  ->method('handle')
- ->with($this->equalTo($request), $this->equalTo(HttpKernelInterface::SUB_REQUEST))
+ ->with($this->equalTo($subRequest), $this->equalTo(HttpKernelInterface::SUB_REQUEST))
  ->will($this->returnValue($response))
  ;