Remove alias as PHPUnit 4.8.35+ ships with it which is supporting PHP 5.3

Author: Seldaek

Psr/Log/Test/LoggerInterfaceTest.php

@@ -2,10 +2,6 @@
 
 namespace Psr\Log\Test;
 
-if (!class_exists('PHPUnit\\Framework\\TestCase', true)) {
-    class_alias('PHPUnit_Framework_TestCase', 'PHPUnit\\Framework\\TestCase');
-}
-
 use Psr\Log\LoggerInterface;
 use Psr\Log\LogLevel;
 use PHPUnit\Framework\TestCase;