[HttpKernel] Remove a duplicate test for the EsiFragmentRenderer

Since the request was made a required argument to the `render()` method in #6829, this test became a duplicate of `testRenderFallbackToInlineStrategyIfEsiNotSupported()`.

src/Symfony/Component/HttpKernel/Tests/Fragment/EsiFragmentRendererTest.php

@@ -19,12 +19,6 @@
 
 class EsiFragmentRendererTest extends \PHPUnit_Framework_TestCase
 {
-    public function testRenderFallbackToInlineStrategyIfNoRequest()
-    {
-        $strategy = new EsiFragmentRenderer(new Esi(), $this->getInlineStrategy(true));
-        $strategy->render('/', Request::create('/'));
-    }
-
     public function testRenderFallbackToInlineStrategyIfEsiNotSupported()
     {
         $strategy = new EsiFragmentRenderer(new Esi(), $this->getInlineStrategy(true));