minor #19998 [DI] Fix expectedException annotation (nicolas-grekas)

This PR was merged into the 3.2-dev branch.

Discussion
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[DI] Fix expectedException annotation

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #19994
| License       | MIT
| Doc PR        | -

@paradajozsef FYI, phpunit (at least v4.8 we have to use for PHP 5.5 compat) doesn't resolve use statements in `expectedException` annotations. Thanks for the fix btw.

Commits
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663bd74 [DI] Fix expectedException annotation

src/Symfony/Component/DependencyInjection/Tests/ParameterBag/EnvPlaceholderParameterBagTest.php

@@ -11,13 +11,12 @@
 
 namespace Symfony\Component\DependencyInjection\Tests\ParameterBag;
 
-use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
 use Symfony\Component\DependencyInjection\ParameterBag\EnvPlaceholderParameterBag;
 
 class EnvPlaceholderParameterBagTest extends \PHPUnit_Framework_TestCase
 {
     /**
-     * @expectedException InvalidArgumentException
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
      */
     public function testGetThrowsInvalidArgumentExceptionIfEnvNameContainsNonWordCharacters()
     {