Merge branch '4.3' into 4.4

* 4.3:
  Remove use of ForwardCompatTrait
  Remove deprecated methods assertArraySubset

Author: nicolas-grekas

Tests/DotenvTest.php

@@ -12,14 +12,11 @@
 namespace Symfony\Component\Dotenv\Tests;
 
 use PHPUnit\Framework\TestCase;
-use Symfony\Bridge\PhpUnit\ForwardCompatTestTrait;
 use Symfony\Component\Dotenv\Dotenv;
 use Symfony\Component\Dotenv\Exception\FormatException;
 
 class DotenvTest extends TestCase
 {
-    use ForwardCompatTestTrait;
-
     /**
      * @dataProvider getEnvDataWithFormatErrors
      */